Amethyst Amethyst is the purple variety of quartz and is one of the most popular gems. If it were not for its widespread availability, Amethyst would be very expensive. Amethyst is a widely used gem.
The name "amethyst" comes from the Greek word "amethustos" which means "not drunken." In the first century, Pliny wrote that amethyst was so named for its color being nearly the same as that of wine. Early Greeks believed that drinking wine from an amethyst cup would prevent intoxication.
Agate Agates in general come in many different forms and are formed in at least five different ways. The main conditions necessary for agate formation, are the presence of silica from denitrified volcanic ash, water from rainfall or ground sources, and manganese, iron and other mineral oxides that form the bands and inclusions.