A student found a pretty rock while hiking with her family. She discovered
that the rock will scratch glass, but not her steel knife.
Mohs Hardness Scale
Take
Gypsum
5
Apatite
6
Orthoclase
Caleite
Fluorite
7
Quartz
8
Topaz
9
10
Corundum Diamond
finger nail penny
glass knife
According to the Mohs Hardness Scale shown above, what does the
student know about the rock? (6.6C, 6.2E)
F. It is harder than quartz, but softer than topaz.
G. It is harder than fluorite, but softer than quartz.
H. It is harder than calcite, but softer than fluorite.