Shomiokite-(Y): Gemstones Information

Shomiokite-(Y) is Na3(Y,Dy)(CO3)33H2O and forms short transparent rose-coloured prismatic pseudohexagonal crystals or granular masses of the orthorhombic system with one direction of perfect cleavage,hardness 2–3 and SG 2.59–2.64. The RI for the alpha, beta and gamma rays is 1.528, 1.529 and 1.531, biaxial positive with birefringence 0.009.Characteristic RE fine absorption lines can be seen and specimens may show a rose-coloured fluorescence under UV. Shomiokite-(Y) occurs with K-feldspar in pegmatites at Mt Alluaiv on the Kola Peninsula,Russia.