The presence of crystals had already come to light in early expeditions during the Spanish conquest. Indeed, two soldiers are documented as having been punished for concealing specimens they believed to be diamonds, although they were actually biterminate quartz crystals

In the early 20th century, a company commissioned to build a harbour on the Gaiba lagoon carried out prospections in the area. They collected what were the first known specimens of Ametrine, some of which have been exhibited in the British Museum ever since. The photograph shows the main shaft at the Ayoreita mine.