Dark Amethyst Crystal with Citrine (Ametrine)

A bolivian Ametrine crystal in darker amethyst-citrine stratigraphy. A rare two-color quartz variety from the only commercial deposit in the world.

Ametrine (also called Bolivianite) is a natural two-zone quartz with a violet amethyst portion and a yellow citrine portion in the same crystal. The two zones are separated by a sharp geometric boundary line.

The only commercially exploitable ametrine deposit worldwide is the Anahí Mine in the Santa Cruz Department, Bolivia. It is located on the border with Brazil in the Pantanal wetlands. According to legend, the mine was discovered by a Spanish conquistador princess Anahí in the 17th century.

The two-color constellation is created by specific temperature-pressure conditions during quartz growth. One part of the crystal grew under citrine conditions, another part under amethyst conditions.