Amethyst

An amethyst is a mineral gemstone that comes from quartz. It is usually transparent and best known for its violet colour. Even though it is a form of quartz, it has more iron oxide (Fe₂O₃) than any other kind of quartz.^[1] Because of this, some experts think that its color comes from the iron in it.^[1]

Heating the amethyst either takes away its color or changes it to a yellow hue. Amethysts are found in Brazil, Uruguay, Canada (Ontario) and America (North Carolina). The rock amethyst is the birthstone of the month February. In the Mohs scale, it has a hardness of seven.^[2]

1. ↑ ^{1.0 1.1} "amethyst (mineral) -- Britannica Online Encyclopedia". britannica.com. Retrieved 27 April 2010.
2. ↑ Cite error: The named reference gemstone was used but no text was provided for refs named (see the help page).