#811

Thanks to member Steve D. in ALBQ NM for mentioning that Zn ores are also a common source of?
Cd.

Testing several species of ore here with the new emphasis on Cd has proved problematic. First the X-Ray hump from the tube is most intense right where Cd K line XRF is located, making it harder to pick out a weak peak there. Strong K peaks- no problem, as shown in one of the pictures to follow.

So I tried looking for L peaks from Cd in? ore.?

First steps are to use pure Cd metal to establish calibration points exactly for 3.2, 3.13, 3.31, 3.52, and 3.71kev.

Then another XRF test of the empty chamber, with no samples inside, for the same time and exposure data.

In all tests for this series, the 3 Al beam filters remain but the final collimator is removed to give a wide beam on the mineral tests to follow. The detector is an Amptek Si-PIN into the Amptek DP5-PC5 electronics stack, then USB to a notebook computer for control and storage.

First the pure metal "stamp"r, X-Ray source set to 37kVp-25uA

CD-Pure-Metal-Stamp-Ka-La-xrf-test-37kVp-25uA-307s-Notes1-small.jpg

CD-Pure-Metal-Stamp-Ka-La-xrf-test-37kVp-25uA-307s-Notes1-small.jpg

In the above, Ka, Kb are in perfect alignment and something is barely detected around 3 keV This rendition (LINEAR) shows how well the K lines are excited in the lighter elements, compared to their L lines.

Geo

CD-Pure-Metal-Stamp-Ka-La-xrf-test-37kVp-25uA-307s-Notes1-small.jpg

CD-Pure-Metal-Stamp-Ka-La-xrf-test-37kVp-25uA-307s.mca

#812

Next a scan of the empty chamber, same parameters but without a sample inside.
CD-Ka-La-xrf-test-307s-37kVp-25uA-NO-SAMPLE-IN-CHAMBER-small.jpg

Then the empty chamber "background with X-Ray ON" with the actual metal XRF together:
RED is the empty chamber with X-Ray ON, the black ghost outline is same parameters but with the pure metal "stamp" in place. Obviously the Cd L lines can be excited and measured in a pure sample. What remains next is to see how well they stand out in an actual ore. Right now I am of a mind that looking for Cd in Zn ore will best be serviced with an isotopic rather than electron exciter source.

Cd-Pure-Metal-Ghost-X-Ray-Source-Only-NO-SAMPLE-RED-BAK.png

Cd-Pure-Metal-Ghost-X-Ray-Source-Only-NO-SAMPLE-RED-BAK.png

Note the blue highlight is an ROI to indicate the area tat Cd L-lines occupy.

Geo

CD-Ka-La-xrf-test-307s-37kVp-25uA-NO-SAMPLE-IN-CHAMBER.mca

CD-Ka-La-xrf-test-307s-37kVp-25uA-NO-SAMPLE-IN-CHAMBER-small.jpg

Cd-Pure-Metal-Ghost-X-Ray-Source-Only-NO-SAMPLE-RED-BAK.png

CD-Ka-La-xrf-test-307s-37kVp-25uA-NO-SAMPLE-IN-CHAMBER.mca

#823

开云体育

Geo,

Sphalerite (ZnS) has an affinity to pick up a lot of different impurities. Here in southern Az Cd is common as one of those impurities. Try running some Sphalerites’ and see what you get.

I also had some Cd in Galena (PbS) at 89 ppm with the Ag running 0.7% (234 oz/ton).?

Dud

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Tuesday, February 18, 2020 7:37 AM
To: [email protected]
Subject: [XRF] Testing for Cd in Zn Ore.

?

Thanks to member Steve D. in ALBQ NM for mentioning that Zn ores are also a common source of?
Cd.

Testing several species of ore here with the new emphasis on Cd has proved problematic. First the X-Ray hump from the tube is most intense right where Cd K line XRF is located, making it harder to pick out a weak peak there. Strong K peaks- no problem, as shown in one of the pictures to follow.

So I tried looking for L peaks from Cd in? ore.?

First steps are to use pure Cd metal to establish calibration points exactly for 3.2, 3.13, 3.31, 3.52, and 3.71kev.

Then another XRF test of the empty chamber, with no samples inside, for the same time and exposure data.

In all tests for this series, the 3 Al beam filters remain but the final collimator is removed to give a wide beam on the mineral tests to follow. The detector is an Amptek Si-PIN into the Amptek DP5-PC5 electronics stack, then USB to a notebook computer for control and storage.

First the pure metal "stamp"r, X-Ray source set to 37kVp-25uA

In the above, Ka, Kb are in perfect alignment and something is barely detected around 3 keV This rendition (LINEAR) shows how well the K lines are excited in the lighter elements, compared to their L lines.

Geo

#825

Will do Dud, thanks I have some of each and will look at them.

Have you seen anything about plutonium detection in trinitite that you can share?

Geo>K0FF

Show quoted text

----- Original Message -----
From: Dude <dfemer@...>
To: [email protected]
Sent: Thu, 20 Feb 2020 12:06:17 -0500 (EST)
Subject: Re: [XRF] Testing for Cd in Zn Ore.

Geo,

Sphalerite (ZnS) has an affinity to pick up a lot of different
impurities. Here in southern Az Cd is common as one of those impurities. Try
running some Sphalerites’ and see what you get.

I also had some Cd in Galena (PbS) at 89 ppm with the Ag running
0.7% (234 oz/ton).?

Dud

From: [email protected]
[mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Tuesday, February 18, 2020 7:37 AM
To: [email protected]
Subject: [XRF] Testing for Cd in Zn Ore.

?

Thanks to member Steve D. in ALBQ NM for mentioning that Zn
ores are also a common source of?

Cd.

Testing several species of ore here with the new emphasis on Cd has proved
problematic. First the X-Ray hump from the tube is most intense right where Cd
K line XRF is located, making it harder to pick out a weak peak there. Strong K
peaks- no problem, as shown in one of the pictures to follow.

So I tried looking for L peaks from Cd in? ore.?

First steps are to use pure Cd metal to establish calibration points exactly
for 3.2, 3.13, 3.31, 3.52, and 3.71kev.

Then another XRF test of the empty chamber, with no samples inside, for the
same time and exposure data.

In all tests for this series, the 3 Al beam filters remain but the final
collimator is removed to give a wide beam on the mineral tests to follow. The detector is an Amptek Si-PIN into the Amptek DP5-PC5 electronics
stack, then USB to a notebook computer for control and storage.

First the pure metal "stamp"r, X-Ray source set to 37kVp-25uA

In the above, Ka, Kb are in perfect alignment and something is barely detected
around 3 keV This rendition (LINEAR) shows how well the K lines are excited in
the lighter elements, compared to their L lines.

Geo

#827

开云体育

Geo,

Pu is best detected with an HPGe detector or via a Fildler using Am-241 as the surrogate. For an alpha detector anything over 20 dpm alpha would go to an alpha spec to determine if it was Pu or radon progeny.? Po 210 tails can cover the Pu 239 depending on the sample, matrix and activities.? Wet chem extraction plated on SS is best for low limit of detection, next best is counting a swipe and then it gets ugly with a solid matrix.? High activity samples can crap up the PIP detector due to kinetic fragment recoil.?

Dud

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Thursday, February 20, 2020 10:05 AM
To: [email protected]
Subject: Re: [XRF] Testing for Cd in Zn Ore.

?

Will do Dud, thanks I have some of each and will look at them.

?

Have you seen anything about plutonium detection in trinitite that you can share?

?

Geo>K0FF

?

Geo,

Sphalerite (ZnS) has an affinity to pick up a lot of different
impurities. Here in southern Az Cd is common as one of those impurities. Try
running some Sphalerites’ and see what you get.

I also had some Cd in Galena (PbS) at 89 ppm with the Ag running
0.7% (234 oz/ton).?

Dud

From: [email protected]
[mailto:[email protected]] On Behalf Of GEOelectronics@...
Sent: Tuesday, February 18, 2020 7:37 AM
To: [email protected]
Subject: [XRF] Testing for Cd in Zn Ore.

?

Thanks to member Steve D. in ALBQ NM for mentioning that Zn
ores are also a common source of?

Cd.

Testing several species of ore here with the new emphasis on Cd has proved
problematic. First the X-Ray hump from the tube is most intense right where Cd
K line XRF is located, making it harder to pick out a weak peak there. Strong K
peaks- no problem, as shown in one of the pictures to follow.

So I tried looking for L peaks from Cd in? ore.?

First steps are to use pure Cd metal to establish calibration points exactly
for 3.2, 3.13, 3.31, 3.52, and 3.71kev.

Then another XRF test of the empty chamber, with no samples inside, for the
same time and exposure data.

In all tests for this series, the 3 Al beam filters remain but the final
collimator is removed to give a wide beam on the mineral tests to follow. The detector is an Amptek Si-PIN into the Amptek DP5-PC5 electronics
stack, then USB to a notebook computer for control and storage.

First the pure metal "stamp"r, X-Ray source set to 37kVp-25uA

In the above, Ka, Kb are in perfect alignment and something is barely detected
around 3 keV This rendition (LINEAR) shows how well the K lines are excited in
the lighter elements, compared to their L lines.

Geo

?