Platinum-group Minerals in Alluvial Deposits.
Sjoberg JJ; Gomes JM
Pres At Precious Metals Conf Reno Nevada, Nov 17-20 1980 Pub in Cal geol 1980 Nov; 34(5):8 pages
The Bureau of Mines is investigating the recovery of byproduct heavy minerals from California sand and gravel deposits as a means of more effectively utilizing these mineral resources. In one phase of the study different platinum-group metal (PGM) minerals are being identified to determine if variations in their geographical distribution exist. Platinum-group mineral concentrates were recovered containing up to 1,000 oz/ton PGM. More than 20 PGM minerals were identified by sem/microprobe analysis of samples from 12 areas of northern and central California. Major minerals identified were ferroplatinum, sperrylite, and osmiridium. Several mineral phases not previously reported in the literature as occurring naturally were tentatively identified. There are indications of the existence of variations in the geographical distribution of the major PGM minerals. The history, occurrence, geology, and uses of the platinum-group metals are discussed.
Pres. At Precious Metals Conf., Reno, Nevada, Nov. 17-20, 1980; Pub. in Cal.geol., V.34,no.5