Re: cyrtolite Little Patsy XRF -Update OT Bassetite
Better scans with an aluminum layer added to the lid, eliminated most of the Pb K line interference-
Note-added 1/4" aluminum layer between shield and its lead lid. Now the uranium K lines are distinct.
Geo
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Re: cyrtolite Little Patsy XRF
OK good, will do that this morning, I had pulled that one out, remembered something about it was difficult.
Geo
----- Original Message ----- From: Charles David Young <charlesdavidyoung@...> To: [email protected]Sent: Mon, 27 Jan 2020 10:18:49 -0500 (EST) Subject: Re: [XRF] cyrtolite Little Patsy XRF
There were a couple that were weak. In particular the bassetite would be good to put under the tube.
Charles Charles, are there any of the rocks you sent me that you would like me to examine under the X-Ray tube before I return this to its original purpose?
I'm sure the only difference we will see between the tube and your method is the time it takes to do the scan.
Geo
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Re: cyrtolite Little Patsy XRF
There were a couple that were weak. In particular the bassetite would be good to put under the tube.
Charles
Charles, are there any of the rocks you sent me that you would like me to examine under the X-Ray tube before I return this to its original purpose?
I'm sure the only difference we will see between the tube and your method is the time it takes to do the scan.
Geo
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Re: cyrtolite Little Patsy XRF
Charles, are there any of the rocks you sent me that you would like me to examine under the X-Ray tube before I return this to its original purpose?
I'm sure the only difference we will see between the tube and your method is the time it takes to do the scan.
Geo
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Re: 2020 Portable X-Ray Tube XRF Outfit.
I'll keep that in mind.? ?It's in the shed right now.? ?I've been running dehumidifier continuously since I got it closed in (mostly,? still needs a bit of caulk) to keep it down to 35% RH.? But it sure couldn't hurt to warm it up first.? ?Kinda like argon lasers...
When you get around to that Nick, you might want to let it run with filaments only for a long time in case it needs to dry out inside before applying HV.
Geo
----- Original Message ----- From: Nick Andrews < nickjandrews@...> To: [email protected]Sent: Sun, 26 Jan 2020 19:24:24 -0500 (EST) Subject: Re: [XRF] 2020 Portable X-Ray Tube XRF Outfit.
Very cool.? ?My Lixi has been sitting in the box since I got it.? ?Need to at least set it up and test run it to make sure it works before getting much more invested.?
Also need to wire up a Glassman HVPS to test fine control of voltage and current.?
Portable, not handheld! LIXI C-Arm X-Ray Head and controller Graded shield/sample chamber Amptek Si-PIN Sensor ![Round-Lid-Open-small.jpg]( "Round-Lid-Open-small.jpg") Lid closed ready to make test run ![Round-Lid-Closed-small.jpg]( "Round-Lid-Closed-small.jpg") Always running near minimum ![46kVp_8uA-small.jpg]( "46kVp_8uA-small.jpg")
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Re: 2020 Portable X-Ray Tube XRF Outfit.
When you get around to that Nick, you might want to let it run with filaments only for a long time in case it needs to dry out inside before applying HV.
Geo
----- Original Message ----- From: Nick Andrews <nickjandrews@...> To: [email protected]Sent: Sun, 26 Jan 2020 19:24:24 -0500 (EST) Subject: Re: [XRF] 2020 Portable X-Ray Tube XRF Outfit.
Very cool.? ?My Lixi has been sitting in the box since I got it.? ?Need to at least set it up and test run it to make sure it works before getting much more invested.?
Also need to wire up a Glassman HVPS to test fine control of voltage and current.?
Portable, not handheld!
LIXI C-Arm X-Ray Head and controller
Graded shield/sample chamber
Amptek Si-PIN Sensor
Lid closed ready to make test run
Always running near minimum
|
Re: 2020 Portable X-Ray Tube XRF Outfit.
Very cool.? ?My Lixi has been sitting in the box since I got it.? ?Need to at least set it up and test run it to make sure it works before getting much more invested.?
Also need to wire up a Glassman HVPS to test fine control of voltage and current.?
Portable, not handheld! LIXI C-Arm X-Ray Head and controller Graded shield/sample chamber Amptek Si-PIN Sensor  Lid closed ready to make test run  Always running near minimum 
|
Re: 2020 Portable X-Ray Tube XRF Outfit.
Geo,
Back down the tube current you¡¯re running 97% Dead Time and way
overloading that detector with pile up . That¡¯s going to create poor
resolution, energy shift and lords knows what other artifacts. Try to keep DT
at 10% or lower. No wonder you¡¯re losing the low E peaks.?
Also the conversion gain is set for a high energy ?of ?61 keV
using 2048 channels and the tube is only capable of 49 kV. That¡¯s 0.03 keV/ch. ?If
you take it down to 50 keV you¡¯ll get 0.02 keV/ch.? If you want to have a
better look at the low energy P, Si, etc turn the beam voltage down to 10 kV and
you can even adjust the conversion gain for a better picture.
Dud
?
toggle quoted message
Show quoted text
From: [email protected]
[mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Sunday, January 26, 2020 12:43 PM
To: [email protected]
Subject: Re: [XRF] 2020 Portable X-Ray Tube XRF Outfit.
?
First run- Torbernite. A 150 second run was made to
establish any self XRF from the uranium in the rock.
Then the exciter was turned on and the run stopped after 5 seconds. Already the
metals had formed their patters, Cu Ka,b, U La,b, Potassium. After a minute
phosphorus could be recognized, but as the test went on the 2 keV peak lost
much of its distinction.
After about 30 seconds, the peaks were formed well enough that an
identification could be made with high confidence. The run was continued for
150 seconds total so that it would be the same as many of our earlier tests
with essentially this same setup.
All .mca files attached and can be viewed with free Amptek DPPMCA or ADMCA
software.
Geo
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Re: 2020 Portable X-Ray Tube XRF Outfit.
Picture labeled for clarity- this is not the cabinet unit that I'm working on, but the original outfit that's been here forever and that you saw in Nevada. Since that field trip several improvements were planned and finally brought together today.? The main shield is something I took out of a junked Xenon Gas monitor, it originally had a pancake tune inside, and a blower to suck air over the tube. It's found duty around here forever and this stop may or may not be its last. The beam enters the bottom, you can see the tube's beryllium window at the bottom of the well. There's a 1/4" lead plate there too, with a central hole, that I added for this application and borrowed from the second layer of my much modified end well probe shield. You might remember that one as the pig with lipstick. One thing I want to experiment with in this rig is the secondary X-Ray exciter. This is when the main beam strikes an intermediate target. then the characteristic X-Rays from that target are routed to the real device under test (DUT) to XRF it. This gives better control of the excitation energy and should also really cut back on the Bremsstrahlung radiation reaching the detector, More later- chow time here///// Geo 
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Re: 2020 Portable X-Ray Tube XRF Outfit.
Geo Nice.
What angles are you using for the Si-Pin to ?the Target and X-ray
tube to the target? ?Do you slide the Sin-Pin in closer when taking the shot.
The distance that is shown here is pretty far away. Getting closer to the
target will get a higher signal due to the increased flux density from a solid
angle
I see you and Charles are using the red protective cap while
running. Have you looked at what the attenuation of the low energy peaks are by
running with and without the cap on a specimen with Al, Si, P, ?S ?and Cl ?
Just shooting soil? in a zip lock plastic bag we can see some changes in the
low end.? For mineral ID Al, Si, P and S are important not to miss.
Dud
?
toggle quoted message
Show quoted text
From: [email protected]
[mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Sunday, January 26, 2020 12:00 PM
To: [email protected]
Subject: [XRF] 2020 Portable X-Ray Tube XRF Outfit.
LIXI C-Arm X-Ray Head and controller
Graded shield/sample chamber
Amptek Si-PIN Sensor
Lid closed ready to make test run
Always running near minimum
|
Re: 2020 Portable X-Ray Tube XRF Outfit.
First run- Torbernite. A 150 second run was made to establish any self XRF from the uranium in the rock.   Then the exciter was turned on and the run stopped after 5 seconds. Already the metals had formed their patters, Cu Ka,b, U La,b, Potassium. After a minute phosphorus could be recognized, but as the test went on the 2 keV peak lost much of its distinction. After about 30 seconds, the peaks were formed well enough that an identification could be made with high confidence. The run was continued for 150 seconds total so that it would be the same as many of our earlier tests with essentially this same setup. All .mca files attached and can be viewed with free Amptek DPPMCA or ADMCA software.  Geo
|
Re: 2020 Portable X-Ray Tube XRF Outfit.
Accessories- Fine tungsten collimator on BEAM  Under Fine Tungsten Collimator is the Broad? Tungsten Collimator, which can be used alone:  The Fine Tungsten Collimator can also be used on the sensor: 
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2020 Portable X-Ray Tube XRF Outfit.
Portable, not handheld! LIXI C-Arm X-Ray Head and controller Graded shield/sample chamber Amptek Si-PIN Sensor  Lid closed ready to make test run  Always running near minimum 
|
Re: cyrtolite Little Patsy XRF
Sounds like a good plan, the Al goes in front the lead in back and sides.?
Let us know what works and what does not work.
Geo
----- Original Message ----- From: Charles David Young <charlesdavidyoung@...> To: [email protected]Sent: Sat, 25 Jan 2020 23:07:22 -0500 (EST) Subject: Re: [XRF] cyrtolite Little Patsy XRF
Ok so this is a good time to ask. I was going to redo the Am241 jig to recess the buttons in an extra layer of lead. Should I add a layer of Al as well? I am thinking the bulk of the interference is coming out the side of the buttons and this is getting back to the detector.
Charles
Understood, and no problem. It's a minor detail, so continue practicing the use of it. The calibration looks spot on!
I'm NOT seeing much 13.95 backscatter, but there is some 17.74 both from NP-237. I should have mentioned, some of this can be eliminated with aluminum shielding between the pellet's business end and the target being tested. Naturally that will also block all the alpha particles but no biggie. Add aluminum foil until the 13.95 and then the 17.74 are significantly reduced, but the 59.5 remains mostly unaffected. I've run this with calibrated absorbers before, but can't remember the thickness offhand, it wasn't much, maybe 0.040"?
Geo
Lately I have been using Am241 all the time. In fact it has been running 24/7 since I got it. I'll read about the low end noise adjustment but frankly I have not touched anything since it arrived. I'll post one tomorrow where I can see Al.
Charles Charles, I agree with Dud on the low end peak, are you making use of the TUNE SLOW/FAST icon button with the source removed after calibrating? It should reset your LLD automatically for you.. If you are and it is leaving the LLD to low so you get noise down there, it can be adjusted by going to the DPP icon (next to HELP icon top line) and open DPP Setup, then select MCA.
Geo
Sent: Sat, 25 Jan 2020 20:15:19 -0500 (EST)
Subject: Re: [XRF] cyrtolite Little Patsy XRF
Charles, Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings. Dud ? ? And here is the last cyrtolite from my collection from Near
Pine, CO: Compared to the South Platte it has more Y and less Fe. ? On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail. The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon? So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf? ? On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal. The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th? ? On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote: I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure. I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note: Yes the Platte is what you called the star twin.? It is
really striking. BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens. So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime? ? El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®: Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual. Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out. I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations? I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample. Branchville was stopped early
once I saw the trend. REE path finder¡¯s Y & Hf? ? El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®: Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ? Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite CpsX1000 ???????????????????????
??? ???????
?????????Vado ??? Patsy????
Platt?????? Cactus????
Branchville ???????????????????????
? Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8 Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4 Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5 Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6 Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5 Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7 U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8 Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ? Platt is generally low which may be a geometry problem There is some variability between them in Zr, Fe, Y, Hf, U and Th Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf. This is a quick first look, it can be tuned a lot better if required. Dud ? ? ? BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch. So what makes Vado interesting? REE path finder¡¯s Y & Hf ? ? Here is the addition of the Burnet County, TX cyrtolite: ? Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite. So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime? I am now scanning the cyrtolite from Cactus Jack. ? Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard? ? On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now. ? On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote: ³¢´Ç´Ç°ì¾±²Ô¡¯
good Dud ? ? I am still running this scan but the element list is now: I have also included an intermediate .mca file. BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238. ? ? It is still early but here are some of the strongest peaks: I'll send the .mca later when I have some decent counts.
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Re: cyrtolite Little Patsy XRF
Ok so this is a good time to ask. I was going to redo the Am241 jig to recess the buttons in an extra layer of lead. Should I add a layer of Al as well? I am thinking the bulk of the interference is coming out the side of the buttons and this is getting back to the detector.
Charles
Understood, and no problem. It's a minor detail, so continue practicing the use of it. The calibration looks spot on!
I'm NOT seeing much 13.95 backscatter, but there is some 17.74 both from NP-237. I should have mentioned, some of this can be eliminated with aluminum shielding between the pellet's business end and the target being tested. Naturally that will also block all the alpha particles but no biggie. Add aluminum foil until the 13.95 and then the 17.74 are significantly reduced, but the 59.5 remains mostly unaffected. I've run this with calibrated absorbers before, but can't remember the thickness offhand, it wasn't much, maybe 0.040"?
Geo
Lately I have been using Am241 all the time. In fact it has been running 24/7 since I got it. I'll read about the low end noise adjustment but frankly I have not touched anything since it arrived. I'll post one tomorrow where I can see Al.
Charles Charles, I agree with Dud on the low end peak, are you making use of the TUNE SLOW/FAST icon button with the source removed after calibrating? It should reset your LLD automatically for you.. If you are and it is leaving the LLD to low so you get noise down there, it can be adjusted by going to the DPP icon (next to HELP icon top line) and open DPP Setup, then select MCA.
Geo
Sent: Sat, 25 Jan 2020 20:15:19 -0500 (EST)
Subject: Re: [XRF] cyrtolite Little Patsy XRF
Charles, Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings. Dud ? ? And here is the last cyrtolite from my collection from Near
Pine, CO: Compared to the South Platte it has more Y and less Fe. ? On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail. The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon? So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf? ? On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal. The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th? ? On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote: I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure. I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note: Yes the Platte is what you called the star twin.? It is
really striking. BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens. So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime? ? El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®: Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual. Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out. I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations? I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample. Branchville was stopped early
once I saw the trend. REE path finder¡¯s Y & Hf? ? El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®: Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ? Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite CpsX1000 ???????????????????????
??? ???????
?????????Vado ??? Patsy????
Platt?????? Cactus????
Branchville ???????????????????????
? Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8 Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4 Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5 Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6 Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5 Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7 U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8 Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ? Platt is generally low which may be a geometry problem There is some variability between them in Zr, Fe, Y, Hf, U and Th Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf. This is a quick first look, it can be tuned a lot better if required. Dud ? ? ? BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch. So what makes Vado interesting? REE path finder¡¯s Y & Hf ? ? Here is the addition of the Burnet County, TX cyrtolite: ? Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite. So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime? I am now scanning the cyrtolite from Cactus Jack. ? Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard? ? On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now. ? On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote: ³¢´Ç´Ç°ì¾±²Ô¡¯
good Dud ? ? I am still running this scan but the element list is now: I have also included an intermediate .mca file. BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238. ? ? It is still early but here are some of the strongest peaks: I'll send the .mca later when I have some decent counts.
|
Re: cyrtolite Little Patsy XRF
Understood, and no problem. It's a minor detail, so continue practicing the use of it. The calibration looks spot on!
I'm NOT seeing much 13.95 backscatter, but there is some 17.74 both from NP-237. I should have mentioned, some of this can be eliminated with aluminum shielding between the pellet's business end and the target being tested. Naturally that will also block all the alpha particles but no biggie. Add aluminum foil until the 13.95 and then the 17.74 are significantly reduced, but the 59.5 remains mostly unaffected. I've run this with calibrated absorbers before, but can't remember the thickness offhand, it wasn't much, maybe 0.040"?
Geo
----- Original Message ----- From: Charles David Young <charlesdavidyoung@...> To: [email protected]Sent: Sat, 25 Jan 2020 22:35:14 -0500 (EST) Subject: Re: [XRF] cyrtolite Little Patsy XRF
Lately I have been using Am241 all the time. In fact it has been running 24/7 since I got it. I'll read about the low end noise adjustment but frankly I have not touched anything since it arrived. I'll post one tomorrow where I can see Al.
Charles Charles, I agree with Dud on the low end peak, are you making use of the TUNE SLOW/FAST icon button with the source removed after calibrating? It should reset your LLD automatically for you.. If you are and it is leaving the LLD to low so you get noise down there, it can be adjusted by going to the DPP icon (next to HELP icon top line) and open DPP Setup, then select MCA.
Geo
Sent: Sat, 25 Jan 2020 20:15:19 -0500 (EST)
Subject: Re: [XRF] cyrtolite Little Patsy XRF
Charles, Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings. Dud ? ? And here is the last cyrtolite from my collection from Near
Pine, CO: Compared to the South Platte it has more Y and less Fe. ? On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail. The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon? So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf? ? On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal. The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th? ? On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote: I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure. I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note: Yes the Platte is what you called the star twin.? It is
really striking. BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens. So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime? ? El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®: Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual. Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out. I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations? I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample. Branchville was stopped early
once I saw the trend. REE path finder¡¯s Y & Hf? ? El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®: Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ? Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite CpsX1000 ???????????????????????
??? ???????
?????????Vado ??? Patsy????
Platt?????? Cactus????
Branchville ???????????????????????
? Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8 Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4 Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5 Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6 Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5 Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7 U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8 Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ? Platt is generally low which may be a geometry problem There is some variability between them in Zr, Fe, Y, Hf, U and Th Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf. This is a quick first look, it can be tuned a lot better if required. Dud ? ? ? BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch. So what makes Vado interesting? REE path finder¡¯s Y & Hf ? ? Here is the addition of the Burnet County, TX cyrtolite: ? Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite. So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime? I am now scanning the cyrtolite from Cactus Jack. ? Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard? ? On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now. ? On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote: ³¢´Ç´Ç°ì¾±²Ô¡¯
good Dud ? ? I am still running this scan but the element list is now: I have also included an intermediate .mca file. BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238. ? ? It is still early but here are some of the strongest peaks: I'll send the .mca later when I have some decent counts.
|
Re: cyrtolite Little Patsy XRF
Lately I have been using Am241 all the time. In fact it has been running 24/7 since I got it. I'll read about the low end noise adjustment but frankly I have not touched anything since it arrived. I'll post one tomorrow where I can see Al.
Charles
Charles, I agree with Dud on the low end peak, are you making use of the TUNE SLOW/FAST icon button with the source removed after calibrating? It should reset your LLD automatically for you.. If you are and it is leaving the LLD to low so you get noise down there, it can be adjusted by going to the DPP icon (next to HELP icon top line) and open DPP Setup, then select MCA.
Geo
Sent: Sat, 25 Jan 2020 20:15:19 -0500 (EST)
Subject: Re: [XRF] cyrtolite Little Patsy XRF
Charles, Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings. Dud ? ? And here is the last cyrtolite from my collection from Near
Pine, CO: Compared to the South Platte it has more Y and less Fe. ? On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail. The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon? So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf? ? On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal. The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th? ? On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote: I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure. I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note: Yes the Platte is what you called the star twin.? It is
really striking. BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens. So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime? ? El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®: Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual. Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out. I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations? I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample. Branchville was stopped early
once I saw the trend. REE path finder¡¯s Y & Hf? ? El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®: Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ? Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite CpsX1000 ???????????????????????
??? ???????
?????????Vado ??? Patsy????
Platt?????? Cactus????
Branchville ???????????????????????
? Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8 Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4 Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5 Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6 Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5 Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7 U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8 Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ? Platt is generally low which may be a geometry problem There is some variability between them in Zr, Fe, Y, Hf, U and Th Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf. This is a quick first look, it can be tuned a lot better if required. Dud ? ? ? BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch. So what makes Vado interesting? REE path finder¡¯s Y & Hf ? ? Here is the addition of the Burnet County, TX cyrtolite: ? Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite. So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime? I am now scanning the cyrtolite from Cactus Jack. ? Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard? ? On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now. ? On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote: ³¢´Ç´Ç°ì¾±²Ô¡¯
good Dud ? ? I am still running this scan but the element list is now: I have also included an intermediate .mca file. BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238. ? ? It is still early but here are some of the strongest peaks: I'll send the .mca later when I have some decent counts.
|
Re: cyrtolite Little Patsy XRF
Charles, I agree with Dud on the low end peak, are you making use of the TUNE SLOW/FAST icon button with the source removed after calibrating? It should reset your LLD automatically for you.. If you are and it is leaving the LLD to low so you get noise down there, it can be adjusted by going to the DPP icon (next to HELP icon top line) and open DPP Setup, then select MCA.
Geo
----- Original Message ----- From: Dude <dfemer@...> To: [email protected]Sent: Sat, 25 Jan 2020 20:15:19 -0500 (EST) Subject: Re: [XRF] cyrtolite Little Patsy XRF
Charles, Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings. Dud ? ? And here is the last cyrtolite from my collection from Near
Pine, CO: Compared to the South Platte it has more Y and less Fe. ? On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail. The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon? So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf? ? On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal. The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th? ? On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote: I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure. I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note: Yes the Platte is what you called the star twin.? It is
really striking. BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens. So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime? ? El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®: Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual. Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out. I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations? I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample. Branchville was stopped early
once I saw the trend. REE path finder¡¯s Y & Hf? ? El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®: Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ? Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite CpsX1000 ???????????????????????
??? ???????
?????????Vado ??? Patsy????
Platt?????? Cactus????
Branchville ???????????????????????
? Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8 Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4 Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5 Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6 Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5 Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7 U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8 Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ? Platt is generally low which may be a geometry problem There is some variability between them in Zr, Fe, Y, Hf, U and Th Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf. This is a quick first look, it can be tuned a lot better if required. Dud ? ? ? BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch. So what makes Vado interesting? REE path finder¡¯s Y & Hf ? ? Here is the addition of the Burnet County, TX cyrtolite: ? Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite. So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime? I am now scanning the cyrtolite from Cactus Jack. ? Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard? ? On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote: Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now. ? On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote: ³¢´Ç´Ç°ì¾±²Ô¡¯
good Dud ? ? I am still running this scan but the element list is now: I have also included an intermediate .mca file. BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238. ? ? It is still early but here are some of the strongest peaks: I'll send the .mca later when I have some decent counts.
|
Re: cyrtolite Little Patsy XRF
Charles,
Look at your low end energy below 1.5 keV. There is a lot of noise
that is killing your count time. The peak at 0 .8 keV is just noise and can be
eliminated by playing around with the peaking time and setting the LLD to a
higher value. Try running a blank back ground and look at the noise. Change the
peaking time (increase it) ?and the fast threshold setting to minimize that.
Then set the LLD to cut off any residual electronic noise. Play with the settings.
Dud
?
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From: [email protected]
[mailto:[email protected]] On Behalf Of Charles David Young
Sent: Saturday, January 25, 2020 2:12 PM
To: [email protected]
Subject: Re: [XRF] cyrtolite Little Patsy XRF
?
And here is the last cyrtolite from my collection from Near
Pine, CO:
Compared to the South Platte it has more Y and less Fe.
?
On Fri, Jan 24, 2020 at 9:58 AM WILLIAM S Dubyk <sdubyk@...> wrote:
Charles,
malacon is cyrtolite is alvite is zircon. This variety of zircon has been given
over a dozen different names in the past, due to the wet chemical analyses that
lumped together the zircon and all of it's inclusions. Since it is usually
metamict, that is, the atomic bonds of the crystals disrupted by alpha
particles, it was difficult to do any structural analyses. I'll send you a
paper that Mark Jacobson did on this years ago that goes into more detail.
The
Wikipedia article on hafnium explains the relationship between Zr anf Hf very
well:
Here is the cyrtolite malacon from Madagascar vs the
cyrtolite from South Platte.? It appears to have relatively more Zr and
less Fe.? Does that comport with malacon?
So I guess what you are saying is that the exsolved minerals
in the inclusions can be almost anything and in this case just happen to be Y,
U, Th (because they don't fit well with other minerals that formed
earlier?).? So why is there such strong association between Zr and Hf?
?
On Thu, Jan 23, 2020 at 7:59 PM WILLIAM S Dubyk <sdubyk@...> wrote:
Charles,
it does not work quite that way. Imagine a crystal lattice, in this case
zircon. Zircon is made from the cations Zr and Hf, and the anions Si and O.
That's it. Cyrtolite, the variety of zircon, is a rapidly forming mineral in a
fluid full of incompatible elements, those that don't fit in well with other
common minerals. Zircon will accept a small portion of these elements into it's
structure, like Y, U, Th, and P. But after a certain point, when that structure
gets strained, the zircon bouncer at the door will say "get out".
Those elements will be exsolved from the structure and then form their own
minerals as inclusions or intergrowths. Remember, elements with the same charge
have different ionic radiuses and those will not fit into the zircon lattice.
What they share is the crystal structure, in this case tetragonal.
The
same things goes for inclusions in columbite such as euxenite/polycrase, or
thorite inclusions in monazite, or argentite inclusions in galena.
What I hear you saying is that if Y is present when
cyrtolite is forming then it will be gladly accepted into the structure as
xenotime just because it is structurally similar.? Does this relate to the
proportion of U and Th?
?
On Wed, Jan 22, 2020 at 10:38 PM WILLIAM S Dubyk <sdubyk@...> wrote:
I
did the gamma spec on these and frankly the Th is quite dominant in some. I use
uranothorite as the standard for comparison. Yes, if the Y gets high enough and
P is available it will form inclusions of xenotime, in fact that is very well
known in zircon. Just like if the Ag gets too high in galena ( PbS), if forms
inclusions of argentite (Ag2S). This is very common in minerals, most do not
accept excessive amounts of an element that does not quite fit in with the
crystal structure.
I
also have Canadian cyrtolites from Davis, MacDonald, JG Gole and Saranac if you
want to take a look at those for comparison.
I had not seen this.? I'll have to take note:
Yes the Platte is what you called the star twin.? It is
really striking.
BTW it seems that you can see the Th content by just doing a
gamma spec.? If the 238 peak is large compared to the other daughters then
it will have high Th content. At least that is the way it appears based on
these few specimens.
So I'll repeat a question about the cyrtolites.? Is the
Y content due to xenotime?
?
El El mi¨¦, ene. 22, 2020 a la(s) 9:41 p.?m., WILLIAM S
Dubyk <sdubyk@...>
±ð²õ³¦°ù¾±²ú¾±¨®:
Pretty
interesting data, folks. U is generally higher in zircon than Th but the north
end of the South Platte is quite different. Other high Th zircons are Mt.
Malosa (Malawi) and SW Oklahoma; got some of those too but they are not
cyrtolite in my opinion. I think the Platt sample is the elbow twin, is that
correct, Charles? I have one more from that area, I think the Luster mine, and
I can send it if you would like to take a look at it; weird looking thing but
labeled as cyrtolite. The Branchville peg in the NE US is a totally different
animal, I do have a some very small specimens of cyrtolite from Maine that are
also pretty unusual.
Vado
is well west of the Cactus, I think that is what Frank said. I think Frank may
have some detailed analyses from the Llano area. We should find out.
I
attached a portion of a talk on the Petaca that Mike Spilde gave at the
Microscopy and Microanalysis convention in Portland on the analyses several
years ago, you will likely understand it more than I do, it does have to do
with standards. I do not think he uses pure samples, maybe for calibration of
concentrations?
I
talked to Mel, he does not have the xrf from NMT, I will get in touch with them
and if they do not, maybe get the analyses done again, I have the sample.
Branchville was stopped early
once I saw the trend.
REE path finder¡¯s Y & Hf?
?
El El mi¨¦, ene. 22, 2020 a la(s) 7:07 p.?m., Dude <dfemer@...> ±ð²õ³¦°ù¾±²ú¾±¨®:
Charles, here¡¯s the Branchville update.? As the gamma spec said, U does
lead the Th.? Branchville could use a longer count. ?
Assuming everything was kept constant here¡¯s the relative concentration for
each cyrtolite
CpsX1000
???????????????????????
??? ???????
?????????Vado
??? Patsy????
Platt?????? Cactus????
Branchville
???????????????????????
?
Zr Kb?????
??5.9?????????
4.4?????????
7.4?????? ? 8.8
Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4
Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5
Fe Ka???? 13.3???????
?7.3?????????
??3.7?????? ? 7.6
Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5
Hf?????????? 2.4?????????
1.4????????? ?
3.9??????? ?4.7
U ???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8
Th????????? ?
6.9?????????
1.4???????? ?
1.5??????? ? 3.5
?
Platt is generally low which may be a geometry problem
There is some variability between them in Zr, Fe, Y, Hf, U and Th
Cactus (Vado) looks pretty good for the most interesting? REE path
finder¡¯s Y & Hf.
This is a quick first look, it can be tuned a lot better if required.
Dud
?
?
?
BTW "Cactus Jack" was initially misidentified when Frank gave it
to me.? He later told me that it is in fact from Vado Ranch.
So what makes Vado interesting? REE path finder¡¯s Y & Hf
?
?
Here is the addition of the Burnet County, TX cyrtolite:
?
Attached are the scans of both cyrtolites from South Platte.? The
latest also has the id of thorite.
So is it fair to say that that Hf, Zr, and Th are common in cyrtolites because
of substitution?? Also, is the Y due to the xenotime?
I am now scanning the cyrtolite from Cactus Jack.
?
Thanks, Steve!? Hm, what is impressive? I have some 99%
zirconium.? Is that what you mean by a standard?
?
On Tue, Jan 21, 2020 at 7:46 PM WILLIAM S Dubyk <sdubyk@...> wrote:
Charles, you
should have it QA'ed by someone else, but wow, that is impressive. Do you have
a zirconium standard? I've got a zirconium disc if you need one.
Ok, here are the final files.? I'll start the other South Platte
cyrtolite now.
?
On Tue, Jan 21, 2020 at 7:17 PM Dude <dfemer@...> wrote:
³¢´Ç´Ç°ì¾±²Ô¡¯
good
Dud
?
?
I am still running this scan but the element list is now:
I have also included an intermediate .mca file.
BTW my gamma scans show this is a combination of U238 and Th232 decay
chains.? I have attached scans of various cyrtolites (including this one)
whose Pb212 peaks at 238keV are relatively large, indicating the presence of
Th232.? The Pb214 peak at 295keV indicates U238.
?
?
It is still early but here are some of the strongest peaks:
I'll send the .mca later when I have some decent counts.
|
Re: cyrtolite Little Patsy XRF
Charles,
Here¡¯s the Near Pine comparison. It does have a lot more Y than
Platt but the Fe content is the same. Th is up too.
Dud
?
CpsX1000
???????????????????????
??? ???????
?????????Vado
???
Patsy???? Platt??????
Cactus???Branchville? Near Pine
???????????????????????
?
Zr Kb?????
??5.9????????? 4.4?????????
7.4?????? ? 8.8???? ??????????? ? 6.9
Zr Ka?????
41.2???????
22.3???????
47.5??????? 90.4???? ??????????? 45.0
Y?????????????
7.5?????????
4.5?????????11.9??????
? 6.5???????????????? 14.4
Fe Ka????
13.3???????
?7.3?????????
??3.7?????? ? 7.6 ??? ??????????? ??7.2????
Fe Kb?????
?2.7?????????
1.6?????? ???
1.5?????? ? 2.5???????????????? ? 2.8
Hf??????????
2.4?????????
1.4????????? ?
3.9??????? ?4.7????????????????? ? 3.2
U
???????????
2.0?????????
1.2?????????
?2.1??????? ? 7.8???????????????? ?
2.0
Th?????????
? 6.9?????????
1.4???????? ?
1.5??????? ? 3.5 ??????????????? ??5.0
?
?
?
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Nick Andrews
