Beryl:Beryl is a mineral that is found in a variety of colours, including green ( emerald), blue (aquamarine), pink (morganite), yellow (heliodor), and white (beryl). It has a Mohs hardness of 7.5-8 and a specific gravity of 2.67-2.78. Beryl is often used in jewellery making, as it is durable and has a high refractive index, which gives it a brilliant lustre.