Riou Bay

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au; Ti
Other commodities Cr
Ore minerals chromite; ilmenite; gold; magnetite; rutile
Gangue minerals garnet; sphene; xenotime; zircon

Geographic location

Quadrangle map, 1:250,000-scale IB
Quadrangle map, 1:63,360-scale D-2
Latitude 59.9079
Longitude -141.4613
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is on the east shoreline of Point Riou Spit, on the west side of Riou Bay. It is in the SW1/4 section 22, T. 23 S., R. 23 E., of the Copper River Meridan. This is sample location 154 of Foley and others (1995).

Geologic setting

Geologic description

Foley and others (1995) collected a beach sample at this location. Spiral concentrate from this sample contained 0.056 gram of gold per ton, 1.07 percent titanium, and 331 ppm zirconium. The heavy-mineral concentrate (12.28 weight percent of the original sample) contained 0.004 percent magnetite, 1.053 percent ilmenite, 0.092 percent garnet, 0.008 percent zircon, 0.007 percent rutile, and 11.12 percent other minerals. Thomas and Berryhill (1962) collected reconnaissance beach samples (IB004, IB006-010) from the Icy Bay area that contained trace to small amounts of magnetite, ilmenite, chromite, zircon, rutile, garnet, sphene, xenotime, and gold. The magnetic fraction of their samples contained as much as 6.2 pounds of iron and 1 pound of titanium oxide per cubic yard. The non-magnetic fraction contained as much as 6.4 pounds, but mostly less than 2 pounds, of titanium oxide per cubic yard.
Geologic map unit (-141.463030920232, 59.9074908907375)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a - beach).
Mineral deposit model number 39a
Age of mineralization Holocene.

Production and reserves

Workings or exploration Reconnaissance characterization of beach samples has been completed in this area.
Indication of production None


MRDS Number 10307628
Reporters Travis L. Hudson
Last report date 12/12/2001