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USGS · 70013969

Straczekite, a new calcium barium potassium vanadate mineral from Wilson Springs, Arkansas

H. T. Evans·G. Nord·J. Marinenko·C. Milton
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Abstract

Straczekite occurs as a rare secondary mineral in fibrous seams, along with other V minerals (A.M. 64-713), in ore from the vanadium mine in Wilson Springs (formerly Potash Sulfur Springs), Garland County, Arkansas. It forms soft, thin laths of dark greenish black crystals up to 0.5 mm in length. Indexed XRD data are tabulated; strongest lines 3.486(100), 10.449(50), 1.8306(50), 1.9437(15) A; a 11.679, b 3.6608, c 10.636 A, beta 100.53o; space group C2/m, C2 or Cm. Chemical analysis gave V2O5 66.4, V2O4 15.3, Fe2O3 0.9, Na2O 0.4, K2O 1.8, CaO 2.5, BaO 5.5, H2O 7.2, = 100.0, leading to the formula (Ca0.39Ba0.31K0.33Na0.11)- 196(V4+1.59V5+6.31Fe3+0.10)O20.02(H2O)2.9; Dcalc. 3.21 g/cm3. A possible layer structure is discussed. The name is for J. A. Straczek, Chief Geologist at Union Carbide Corp.-R.A.H.

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Mineralogical MagazineArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 36.146746777814364° to 36.4433803110554° latitude; -93.53485107421875° to -92.449951171875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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H. T. Evans, G. Nord, J. Marinenko, C. Milton. 2018-07-05. Straczekite, a new calcium barium potassium vanadate mineral from Wilson Springs, Arkansas. https://doi.org/10.1180/minmag.1984.048.347.16

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