Good day Jack,

When it comes to minerals I usually use:

Manual of Mineralogy (after James D. Dana), 21st Edition, Revised (Hardcover)

Which can be bought from amazon.com cheaply. It has indepth information regarding minerals and their hardness.

Most engineers use the Vickers or Knoop tests when talking about other materials such as steel or ceramics.

Let me know if you have any further questions.

Best Regards,

Todd Danielczyk

General Kinematics Corporation ■

Hello Jack,

Sometimes Wikipedia can help out.

Try f.i.

http://en.wikipedia.org/wiki/Calcium

have a nice day

Teus ■

Jack,

I had a chance to think about this some more and

http://www.webmineral.com/determin.shtml

will give you all the answers you would need when it comes to minerals.

Todd Danielczyk

General Kinematics Corporation ■