Sergeysmirnovite, MgZn2(PO4)2 · 4H2O, a New Mineral from the Kester Deposit (Sakha-Yakutia, Russia).

Sergeysmirnovite, MgZn₂(PO₄)₂ · 4H₂O, is a new mineral from the oxidation zone of the Kester mineral deposit, Sakha-Yakutia, Russia. This mineral forms tabular colorless crystals growing on quartz and fluorapatite aggregates in association with pseudomalachite, libethenite, native copper, a Na-analogue of batagayite, arsenolite, tobermorite, epifanovite, and batagayite. The mineral is orthorhombic, with the space group Pnma. The unit cell parameters refined from powder X-ray diffraction data are the following: a = 10.5957(6) Å, b = 18.365(1) Å, c = 5.0320(4) Å, V = 979.16 (8) ų. The eight most intense powder X-ray diffraction lines are the following (I-d[Å]-hkl): 100-5.28-200; 33-4.576-040; 24-3.999-230; 24-3.877-031; 22-3.387-221; 44-3.015-250; 57-2.854-311; 34-2.647-400. Sergeysmirnovite belongs to the hopeite group and is dimorphous with reaphookhillite. The mineral is named in honor of famous Soviet geologist, Academician Sergei Sergeevich Smirnov (1895–1947), a renowned specialist in the mineralogy of ore deposits. [ABSTRACT FROM AUTHOR]