Cindy(posted 9671 days ago)Well you asked:
Hardness-harder than your fingernails
Color-under a new moon the rock has to be dark.
Pattern of surface color-the more the better
Specific Gravity->1, i.e. must not float on water.
Texture-smooth and rough
Size-depend on your mental state.
I however have found that the uglier the better, scouts working on the geology merit badge will over look. but the best one are the ones that you trip over.