Hardness

1. What is hardness?
Hardness is defined as resistance to scratching.

2. What scale do we use to judge it?
The Moh's scale.

3. List the order of increasing hardness on the scale with an example at each level.
Talc(1), gypsum(2), calcite(3), fluorite(4), apatite(5), orthoclase(6), quartz(7), topaz(8), corundum(9), diamond(10).

4. What is considered to be the minimum acceptable hardness for a gemstone?
7. Stones with a hardness less than 7 will scratch more easily so how they are fashioned into jewelry and how they are cared for is important.