The amethyst is a variety of quartz known for its characteristic violet colour which can be more or less dark. For example, Siberian grade amethysts have reddish hues and are the most highly prized variety. This gemstone was already being worked and used in jewellery in Ancient Egypt and is associated with power: it was one of the favourite gemstones of Russia's Catherine the Great and is often worn by bishops and cardinals.
Color: purple, violet
Moh's hardness: 7
Chemical composition:SiO2 Silicon dioxide