Yes.
A rare mineral that can be cut and polished could be called a gemstone.
its a gemstone
Yes.
This would be called a gemstone.
crystals
Diamond
a gem
As diamond is the hardest natural mineral on earth, theoretically, only diamond can cut a diamond. But, diamonds are also cut by lasers. Diamonds are cut and polished on diamond wheels. They are held against a rotating plate which is made from hardened steel infused with diamond dust.
Diamond. Diamond is, for example, polished with diamond powder.
A cut and polished, commercial diamond is valued by its cut, clarity, carat weight and colour. A real diamond conducts electricity, is the hardest mineral known and comes in many natural colours, depending on what other trace minerals are present in the stone.
They are ground on "Diamond wheels" and laped with "Diamond dust" then polished.
Diamonds cut because diamond is the hardest mineral known.