Inderite: Gemstone Information
Inderite scarcely has ornamental potential; it is colourless, soft (H2.5) and the surface is likely to suffer cloudiness or to develop a whitish appearance after fashioning. Inderite is MgB3O3(OH)55H2O and forms long prismatic crystals of the monoclinic system with one direction of perfect cleavage which leaves behind a notably pearly surface. The SG is near 1.79 and the RI for the alpha, beta and gamma rays is 1.488, 1.491, 1.505,biaxial positive with a birefringence of 0.017. Inderite is dimorphous with kurnakovite (q.v.) and occurs in lacustrine borate deposits. The main source of both minerals is Inder Lake, Kazakhstan.