Another example - Mineral 13

Distinguishing Physical Properties:  

• Ignore the black minerals in this sample.

• The first thing that I notice is the distinctive yellow-green (olive) color.

• Even though it's a large sample, if you look closely it looks like a lot of small particles cemented together (not unusual).

• If you could test this sample, you would find that it scratches glass (>5.5 hardness).