The growth of γ-MnS crystals in sodium silicate gels

Abstract Single crystals of γ-MnS and α-MnS have been grown in silica gels at temperatures between 4° and 41°C. Tabular hexagonal crystals of γ-MnS up to 1 mm across have been characterized optically, spectrochemically, and by x-ray diffraction. γ-MnS is uniaxial positive, with a birefringence of approximately 0.022–0.032.