Commodities
PrimarySilver, Gold, Zinc, Copper, Lead
Commodity typeM
Deposit
Deposit sizeN
Ore controlThe Deposit Is In A Breccia Pipe. Strongly Brecciated And Partially Rotated Fragment Of Quartz Diorite As Much As 3 Cm Long Are In A Matrix Of Quartz, Tourmaline, Calcite, Pyrite, And Chalcopyrite. The American Flag Deposit Is Part Of The Mazama Porphyry Copper-Molybdenum System (Riedell, 1979).
Materials
Ore mineralsChalcopyrite, Sphalerite
GangueCalcite, Pyrite, Quartz, Sericite, Tourmaline
Geology
Host rockDiorite
Tectonic settingMagmatic Arc Rocks Of The Area Include The Fawn Peak Stock, Which Is Probably The Intrusive Equivalent Of The Volcanic Member Of The Midnight Peak Formation. The Stock Was Probably The Intrusive Rock Core Of An Island Arc (Riedell, 1979). The Unit Has Yielded K-Ar Magmatic Biotite Ages Of Approximately 988 M.Y. (Stoffel, 1990, P. 28).
Economic & production
Development statusOccurrence
Identification
Deposit ID10055965
MRDS IDSP00187
Alternate namesOriental, Central;
RegionNA
Data scoreB
Coordinates48.59289, -120.38702
References
HUNTTING, M. T., 1956, INVENTORY OF WASHINGTON MINERALS-PART II, METALLIC MINERALS: WASHINGTON DIVISION OF MINES AND GEOLOGY BULLETIN 37, V. 1, 428 P.; V. 2, 67 P.RIEDELL, K.B., 1979, GEOLOGY AND PORPHYRY COPPER MINERALIZATION OF THE FAWN PEAK INTRUSIVE COMPLEX, METHOW VALLEY, WASHINGTON: UNIVERSITY OF WASHINGTON MASTER OF SCIENCE THESIS, 52 P., 4 PL.STOFFEL, K.L., MCGRODER, M.F., COMPILERS, 1990, GEOLOGIC MAP OF THE ROBINSON MOUNTAIN 1:100,000 QUADRANGLE, WASHINGTON: WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES OPEN-FILE REPORT 90-5, 39 P., 1 PL.WDGER OF 90-18