Chivinar is a 5,125 metres (16,814 ft) high Late Miocene volcano in Northwest Argentina. The volcano is noted for having erupted rhyolites containing topaz in its early stage of evolution, the only known occurrence of such in South America. This topaz did form during the crystallization of the magma in a fluorine-rich phase thereof at low temperatures and pressures. The topazes reach sizes of 8 centimetres (3.1 in). The topaz bearing rocks cover a surface area of 8 by 4 kilometres (5.0 mi × 2.5 mi) that is interrupted by a lava flow. Much older granitoid bodies also lie in the area and are 502-425 million years old.