Sarvodaite Al ₂ (SO ₄ ) ₃ ⸱5H ₂ O, a new mineral from the Fan-Yagnob coal deposit, Tajikistan

A new hydrous aluminium sulfate mineral sarvodaite, Al 2 (SO 4 ) 3 5H 2 O, was discovered at the tract of Kukhi-Malik, Fan-Yagnob coal deposit, ca.75 km N of Dushanbe, Tajikistan.Sarvodaite is a fumarolic mineral formed directly from gas from a natural underground coal fire.Associated minerals are anhydrite, realgar, native selenium and several unknown phases.The mineral typically occurs as white spherolites of thin colorless prismatic crystals up to 500 m in maximum dimension.Sarvodaite is optically biaxial, = 1.529(2), = 1.537(2), (calc.)= 1.545(3) (590 nm), and the measured 2V is 90(3).The measured density is 2.33(2) g/cm 3 .The mineral is non-soluble in water and ethanol and dissolves slowly at room temperature in HCl.The composition of sarvodaite was studied using EDS.Raman and IR spectroscopy confirmed the presence of H 2 O.The empirical formula calculated on the basis of 17 O atoms per formula unit is (Al 1.88 Fe 0.06 Ti 0.04 ) 1.98 S 3.01 O 12 5H 2 O.