They are visually stunning and have been in demand for many centuries. Its name derives from the Greek "amethystos", which means "not drunken", as Amethyst in ages past was thought to ward off drunkenness. This gemstone is also said to protect its wearer against seduction. Moses described it as a symbol of the Spirit of God in the official robes of the High Priest of the Jews. If this stone were not so readily available it would be extremely expensive based upon demand.

The color of some Amethyst may slowly fade upon constant exposure to light. Amethyst changes color when it is heated. Amethyst is sometimes heat treated to deepen its color, or to transform it into Citrine. The color of certain varieties can change to a light green color, which is called "Prasiolite". Smoky colored stones can be transformed to a yellow to brownish-red and clear ones may become yellow. The natural geothermal heating sometimes creates multi-color stones, like the specimens found in Bolivia, a variety called Ametrine.

Brazilian Amethyst crystals are attractive to look at and form in drusy coatings that line the inside of sometimes large volcanic pockets or “vugs”. Some of the vugs form from trees that were engulfed in a lava flow while other vugs are gas bubbles trapped in the lava. Brazilian vugs can be very large and form crystals that are pale lavender to dark purple in color. The quality of these for gemstones is not as good as others due to the fact that the color is not consistent throughout the crystal but is on the outer surfaces and on the tops of the crystals. Most clusters form with gray, white and blue agate and have a green exterior on the vugs. Inclusions of calcite and cacoxenite are common.

African Amethyst crystals are usually large but not as attractive as Brazilian Amethyst. However, the interior color and clarity are excellent and polished slices and carvings as well as many gemstones from Africa are prized and admired. Colors range from very pale lavender to a very dark purple. Most of the South African Amethyst is formed in vugs of white or tan, to light grey basalt.

Uruguay Amethyst from the Artigas area is the most sought after locale. The specimens from Artigas are more pure and a deeper, richer color than most finds. Artigas amethyst is found as vugs deep in hard rock base and requires major excavation to find the geode like vugs of amethyst. Until 1999 this amethyst was hand dug or excavated with small machinery. Specimens have been sold through Idar-Oberstein German markets for many years.