Commodities
PrimaryFeldspar, Beryllium, Mica, Lithium
SecondaryTantalum
Commodity typeB
Deposit
Deposit sizeS
WorkingsSurface
Orebody formIRREGULAR-SHAPED DIKE
Materials
Ore mineralsAmblygonite, Beryl, Columbite, Feldspar, Muscovite
GangueCleavelandite, Quartz, Sericite, Spodumene, Tourmaline, Triphylite, Uraninite, Uranophane
Geology
Host rockMica Schist · Quartz Two-Mica Schist
Associated rockPegmatite · Pegmatite
StructureBlack Hills Uplift
AlterationSpodumene Is Highly Altered. Albite Has Replaced Microcline
Economic & production
Development statusPast Producer
First production1934
Discovery year1932
Identification
Deposit ID10055678
MRDS IDSD02291
RegionNA
Data scoreB
Coordinates43.85218, -103.61946
References
U.S. BUREAU OF MINES, 1955, BLACK HILLS MINERAL ATLAS, SOUTH DAKOTA: PART 2, BUREAU OF MINES INFORMATION CIRCULAR 7707FISHER, D. JEROME, 1945, PRELIMINARY REPORT ON THE MINERALOGY OF SOME PEGMATITES NEAR CUSTER, SOUTH DAKOTA GEOLOGICAL SURVEY REPORT OF INVESTIGATIONS 50FISHER, D. JEROME, 1942, PRELIMINARY REPORT ON SOME PEGMATITES OF THE CUSTER DISTRICT, SOUTH DAKOTA GEOLOGICAL SURVEY REPORT OF INVESTIGATIONS 44ROBERTS, W.L., AND RAPP, GEORGE, 1965, MINERALOGY OF THE BLACK HILLS, SOUTH DAKOTA SCHOOL OF MINES AND TECHNOLOGY BULLETIN 18