Most gems are “minerals that have been chosen for their beauty and durability, then cut and polished for use as human adornment.” This definition covers the vast majority of the stones we regard as gems.Gemstones have their own science called gemmology, which is a branch of mineralogy. The concept of a gemstone is based on human value judgements. A gemstone is usually defined as a highly attractive and valuable piece of cut and polished mineral used in jewellery or other decorations.
Beauty:- Beauty isn’t necessarily in the eyes of the beholder. There are gems some don’t consider beautiful, like a gem that may be pink or olive green.
Durability:- Durability is usually a high priority while buying or choosing a gemstone/s. Pearls are generally considered to have a life span of about a century,that is because they are soft and the simple act of wiping the dust off of them slowly wears the surface coating away.
Opals have been one of the most prized gems throughout history, but they are notoriously delicate. They have water content and, as they dry out, they may crack. Opals are also fragile and can break with the slightest bump.