Seattle-Cascade

Occurrence in King county in Washington, United States with commodities Silver, Lead, Zinc, Copper, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Host and associated rocks
  9. Nearby scientific data
  10. Controls for ore emplacement
  11. Economic information about the deposit and operations
  12. Mining district
  13. Links to other databases
  14. Bibliographic references
  15. Reporter information

Geologic information

Identification information

Deposit ID 10055932
MRDS ID SP00144
Record type Site
Current site name Seattle-Cascade
Alternate or previous names Triple S, Silver Dollar, Copper Plate, Silver Dollar and Copper Plate;
Related records 10048622, 10204478

Geographic coordinates

Geographic coordinates: -121.41953, 47.66814 (WGS84)

Site location context

Political divisions (FIPS codes)

King(county)

Washington(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Grotto(quadrangle 1:24,000 scale)

Skykomish River(quadrangle 1:100,000 scale)

Wenatchee(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Skykomish(hydrologic unit)

Puget Sound(hydrologic accounting unit)

Puget Sound(hydrologic subregion)

Pacific Northwest(hydrologic region)

Federal lands

Mt. Baker-Snoqualmie National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Alpine Lakes Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Washington King

Public Land Survey System information

Meridian Township Range Section Fraction State
025N 011E 17 N2 Washington

Comments on the location information

  • WEST OF THE MILLER RIVER

Commodities

Commodity Importance
Silver Primary
Lead Primary
Zinc Critical Primary
Copper Primary
Gold Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Sphalerite Ore
Pyrite Gangue
Quartz Gangue

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Tonalite
    Stratigraphic age (youngest) Miocene

Nearby scientific data

(1) -121.41953, 47.66814

Economic information

Controls for ore emplacement

  • Mineralization Occurs In A 1.5-Ft-Wide Shear Zone In Granodiorite, In Bands As Much As 8-In-Thick And Which Assay As Much As 30 Oz/Ton Ag (Moen, 1976, P. 167).

Comments on the geologic information

  • THE SEATTLE-CASCADE MINE IS IN ROCKS OF THE SNOQUALMIE BATHOLITH, NORTHERN PHASE, WHICH CONSISTS OF GRANODIORITE AND TONALITE AND IS LIGHT COLORED, MEDIUM CRYSTALLINE, AND MOSTLY EQUIGRANULAR AND HAS HYPIDIOMORPHIC TEXTURE. THE ROCKS ARE COARSELY JOINTED AND CONTAIN BIOTITE AND HORNBLENDE AND LOCALLY CLINOPYROXENE. AGE OF THE NORTHERN PHASE IS ABOUT 25 M.Y. BASED ON INTERPRETATION OF NUMEROUS DISCORDANT K-AR AGES OF BOTH HORNBLENDE AND BIOTITE (TABOR AND OTHERS, 1982, P. 8).

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Significant No

Mining district

District name Miller River

Comments on development

  • ECON.COM: MINOR PRODUCTION PRIOR TO 1900; PRODUCED AGAIN IN 1940 (HUNTTING, 1956, P. 297).

Reference information

Bibliographic references

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JAN-1991 Berger, Mary A. U.S. Geological Survey
Updater 01-DEC-1992 Frank, Dave U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.