Quartz that displays bands of both purple and yellow is known as ametrine. Gem-quality ametrine is sourced from only a single site in Bolivia. Emerald cuts and fantasy carvings are popular ways to showcase the dramatic color zoning in this very durable gemstone.
Ametrine prices are rather modest. As far as the material itself, the depth and vividness of colors and the distinction of the color separation are the main value points.
Although ametrine was first reported from Rio Grande do Sul, Brazil, the Anahí Mine in Bolivia currently produces all the known, gem-quality material. The native peoples of the region have long valued this stone. However, the mine was seemingly lost to commercial interests after the 17th century and not rediscovered until the 1960s. Non-commercial deposits have also been found in the United States, Canada, India, and Mozambique.