|What is a gemstone?
It’s a mineral, rock, or petrified material that when cut/ faceted and polished is collectible or can be used in Jewellery. Others are organic – amber (fossilised tree resin); and jet (a form of coal).
How are they classified?
Gems are classified into different groups, species or varieties. Take the ruby. It’s the red variety of the species corundum, while any other colour of corundum is considered sapphire.
Emerald, aquamarine, bixbite, goshenite, heliodor and morganite, are all varieties of the mineral species beryl.