Artificial argentojarosite, ag2fe6(oh)12(so4)4, prepared in connection with Bureau of Mines research on refractory silver ores, has been synthesized in considerably greater quantities than in previous studies. As a result, a detailed study of its thermal decomposition, optical properties, and physical properties was possible by a combination of chemical analyses, differential thermal analyses, x-ray diffraction, and optical techniques. Cell dimensions are a = 7.347 (+/-0.010), C = 16.580 (+/-0.053); Refractive indices are e = 1.789-1.790, W = 1.889-1.890. Twenty- nine observed x-ray diffraction reflections including reflection indices, relative intensities, and observed and calculated d- spacings are listed.
Am. Mineralogist, V. 58, September-October 1973, PP. 936-941