Believe it or not granite has many different harness to it. Now the talc is the softest of the minerals can be easily scratched with your fingernail and it is used in paints, and talcum power. Calcite is a little harder on the scale of hardness, you can barely scratch it with a copper penny and is used in limestone. Moving on up the scale of harness apatite you can barely scratch it with a
. knife blade and this is used in common fertilizers. Moving on up to the scale to quartz it is a common mineral and often one of most pretty ones, it can easily mark steel and hard glass and used as gemstones. If you visit this site http://www.natural-stone-interiors.com/granite-countertop.html you can see a list of others and their uses.
