Procedure
1) Gather all the materials. See Material List.
2) With each mineral, perform a scratch test with a finger nail. Record the results.
3) With each mineral, perform a scratch test with a copper penny. Record the results.
4) With each mineral, perform a scratch test with the glass sheet. Record the results.
5) With each mineral, perform a scratch test with a steel knife. Record the results.
6) With each mineral, perform a scratch test with sand paper. Record the results.
7) With each mineral, perform a scratch test with an emery board/steel file. Record the results.
Performing a scratch test using a knife.