Pyramidal but prismatic habit crystals of tin stone from East Transbaikal

Abstract

The study of pegmatite deposits of tin stone from East Transbaikal gave a number of results indicating a connection between the form and genesis of this mineral. A number of cassiterite crystals found in pegmatite veins confirm the connection of pyramidal crystals with high-temperature formation conditions. The described high-temperature crystals of tin stone from the Zavitinsky deposit were of interest, having a prismatic appearance that is characteristic of low-temperature pegmatites. Measurements of a single crystal showed that it is a dipyramid with angles between the normals to the faces of the dipyramid equal to 58°16'. "Fedorovsky Institute"