Peterandresenite is a very rare mineral, the first known natural hexaniobate. Its chemical formula is Mn4Nb6O19•14H2O. Its structure contains a special type of octahedron: Lindqvist ion. Peterandresenite was found in a pegmatite of the Larvik complex in Norway.Friis, H., Larsen, A.O., Kampf, A.R., Evans, R.J., Selbekk, R.S., and Sánchez, A.A., 2014. Peterandresenite, Mn4Nb6O19·14H2O, a new mineral containing the Lindqvist ion from a syenite pegmatite of the Larvik Plutonic Complex, southern Norway. European Journal of Mineralogy 26, 567-576 It is somewhat similar to other unique niobium minerals, aspedamite and menezesite.
Occurrence Peterandresenite was discovered in AS Granit quarry, Tvedalen, Larvik, Vestfold, Norway.
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