COLLECTION AND JEWELLERY CASSITERITES OF THE IULTIN DEPOSIT

The large crystals of the collection and jewellery quality (including the crystals unique by size) have been found at the Iultin deposit (Eastern Chukotka). The jewellery ones are connected with veined morphological type of the ore bodies and located in the mineralized cavities and muscovite fringes. A black colour of cassiterite is conditioned by large number of the zones of the growth which absorb passing light. Significant by volume colourless and different-coloured fragments can be found in crystals. They can be used for faceting of high quality. The cassiterite of collection and jewellery quality is an important factor of profitability's raising in exploitation of tin deposits.