Description
PEROVSKITE CRYSTALS
This is the cubic grayish-black perovskite crystals in chlorite schist. Dimensions: 2.2 x 1.4 x 0.8″ (5.5 x 3.5 x 2cm). Weight – 1.8oz (51 grams). Origin: Russia, Ural.
Some information about perovskite:
Perovskite is a calcium titanium oxide mineral composed of calcium titanate (CaTiO3). Its name is also applied to the class of compounds which have the same type of crystal structure as CaTiO3 (XIIA2+VIB4+X2?3), known as the perovskite structure. Many different cations can be embedded in this structure, allowing the development of diverse engineered materials.
The mineral was discovered in the Ural Mountains of Russia by Gustav Rose in 1839 and is named after Russian mineralogist Lev Perovski (1792–1856). Perovskite’s notable crystal structure was first described by Victor Goldschmidt in 1926 in his work on tolerance factors. The crystal structure was later published in 1945 from X-ray diffraction data on barium titanate by Helen Dick Megaw.
Found in the Earth’s mantle, perovskite’s occurrence at Khibina Massif is restricted to the silica under-saturated ultramafic rocks and foidolites, due to the instability in a paragenesis with feldspar. Perovskite occurs as small anhedral to subhedral crystals filling interstices between the rock-forming silicates.
