Amethyst
Natural stone
Purple quartz, coloured by iron and natural irradiation. Hard enough for most jewellery; strong sunlight and heat can fade it, and much amethyst is heated to deepen or change the colour.
Hardness (Mohs): 7
Natural stone
Purple quartz, coloured by iron and natural irradiation. Hard enough for most jewellery; strong sunlight and heat can fade it, and much amethyst is heated to deepen or change the colour.
Hardness (Mohs): 7