Question

What makes a mineral a gem?

Answer 1

The mineral should be hard and tough to resist scratching and have beautiful clarity or colour. The value is based on rarity and rare quality.

Answer 2

Minerals are made from elements that are substances which cannot be broken down into any simpler form.

Whereas a gemstone, also called a gem, is a piece of mineral in crystalline form.

For a mineral to be categorized as a gem, a naturally occurring mineral should  be clear with a beautiful color and hard enough to resist any scratches. It is then cut and polished into a stone form to be used as a piece of jewelry.