ISOVITE (Cr, Fe)_(23)C_6 - THE NEW MINERAL FROM THE GOLD-PLATINUMBEARING PLACERS OF THE URALS

摘要

An unknown Fe-Cr carbide has been found out while the study of heavy concentrate processed form the gold-platinum placer sand. The new mineral was named isovite according to the place of its finding- Isovsky district of the Central Urals. It has been discovered within polyphase grains revealed in the concentrate together with native gold, copper-bearing gold, various PGM minerals, cinnabar and chromspinelides. The total scope of material for analyses was presented by 12 grains (named A, B, C, …L, M). By recounting for 29 atoms, the formula of isovite is as following: (Cr_(16.2)Fe_(6.0)Ni_(0.1))C_(6.7). Density 7.4 g/cm~3; cubic symmetry system. Unit cell parameters (Fm3m): a==10.65+0.05 A V=1208 A~3. Standard specimen of isovite is in the A.E. Fersman Mineralogical museum, Moscow.