Amethyst is a variety of Quartz, the best examples of which are found in Brazil, Siberia and Sri Lanka. Natural Amethyst is a violet colour with red or blue tones.
Amethyst was once considered to be more valuable than Diamond. It is often referred to as "Nature's Tranquilliser" due to its calming effect.
It has been used as a healing stone since Neolithic times, and Ancient Romans decorated their goblets with the stone to ward off drunkenness.