Rutile after Anatase

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A set of two pseudomorph specimens, now replaced by crystallized rutile. The size provided is in average for the two pieces.Diamantina, located in the Jequitinhonha Valley of Minas Gerais, Brazil, is a historic diamond- and quartz-mining district with operations dating back to the early 18th century during the Portuguese colonial era. Geologically, the area is characterized by the ancient quartzites, schists, and conglomerates of the Espinhaco Supergroup, which were subjected to extensive regional metamorphism and hydrothermal activity. Mineralogically, the district is world-famous for its exceptional quartz crystals, including hematite-inclusions and skeleton growth forms, and is especially renowned for pseudomorphs of rutile after anatase, where anatase crystals are completely replaced by granular or acicular rutile while retaining their original crystal geometry.