These test kits are available in different forms but they all work in the same way. A pointed pick is used
to try to scratch the mineral or object being tested. Starting with #1, increasing numbers are tried until one does scratch the test material, indicating the harness of the material is less than the point that does actually scratch
it but more than the previous point that did not.
The set I use and take on field trips came in a sturdy wooden case as shown. It came from a mining/prospecting outfitter that used to be in business in Las Vegas, located right next to my favorite Mexican restaurant.
Some of these picks make excellent XRF targets, so in the following posts I will attach XRF scans of them starting with #9 and my amateur attempt to identify the materials that make them.
Have fun,
Geo>K0FF
