Hyder Mica

Prospect in Alaska, United States with commodities Mica, Feldspar
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Nearby scientific data
  8. Economic information about the deposit and operations
  9. Mining district
  10. Links to other databases
  11. Bibliographic references
  12. General comments
  13. Reporter information

Geologic information

Identification information

Deposit ID 10308991
MRDS ID A012414
Record type Site
Current site name Hyder Mica
Alternate or previous names Last Chance, Nakat Mica, Nakat Feldspar, Pegmatite Mica, Pearson, Mica City, Mrs. Mack
Related records 10001643

Geographic coordinates

Geographic coordinates: -130.71372, 54.77575 (WGS84)
Relative position This site (Elliott and others, 1978, locs. 175-182) consists of eight occurrences in the Nakat Bay-Sitklan Passage area, all of which have been prospected for mica. Six of the prospects, known only from U.S. Bureau of Mines (1974) claim records, are named: Nakat Mica (Elliott and others, 1978, loc. 175; Sec 35, T. 81 S., R. 98 E., of the Copper River Meridian); Nakat Feldspar (loc. 176; Sec 35, T. 81 S., R. 98 E., of the Copper River Meridian); Pegmatite Mica (loc. 177; Sec 12, T. 82 S., R. 98 E., of the Copper River Meridian); Pearson (loc. 178; Sec 12, T. 82 S., R. 98 E., of the Copper River Meridian); Mica City (loc. 179; Sec 12, T. 82 S., R. 98 E., of the Copper River Meridian); and Mrs. Mack (loc. 181; Sec 18, T. 82 S., R. 99 E., of the Copper River Meridian). The two remaining prospects (Sainsbury, 1957, p. 156-159) are named Last Chance (Elliott and others, 1978, loc. 180; Sec 13, T. 82 S., R. 98 E., of the Copper River Meridian); and Hyder Mica (loc. 182; Sec 18, T. 82 S., R. 99 E., of the Copper River Meridian). The coordinates are for the approximate center of the estimated four-square-mile area that encompasses this group of prospects; the coordinates of the center are accurate within about 0.2 mile.

Site location context

Political divisions (FIPS codes)

Prince of Wales-Hyder(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Prince Rupert D-3(quadrangle 1:63,360 scale)

Duke Island(quadrangle 1:100,000 scale)

Prince Rupert(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Southern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Misty Fiords National Monument Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Tongass National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Misty Fjords National Monument Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Mica Primary
Feldspar Secondary

Materials information

Materials Type of material
Quartz Gangue

Nearby scientific data

(1) -130.71372, 54.77575

Economic information

Comments on the geologic information

  • Geologic Description = The Nakat Bay-Sitklan Passage area (Sainsbury, 1957, p. 152-161; Berg and others, 1988) is underlain by intensely folded and faulted Mesozoic or Paleozoic sedimentary, volcanic, and intrusive rocks that are regionally metamorphosed to greenschist and amphibolite grade. The metamorphic rocks locally are replaced or intruded by quartz-feldspar-mica pegmatite bodies that in places contain books of muscovite mica as much as eight inches in diameter (Sainsbury, 1957, p. 152-161; Cobb and Elliott, 1980, p. 142-143). Massive pegmatite bodies at the Hyder Mica prospect (Sainsbury, 1957, p. 156-159) locally contain mica plates as much as 8 inches in diameter. The deposit was explored in the 1950s(?) by five trenches and several pits. Some of the mica was classified by state and federal agencies as 'strategic muscovite mica,' but most was of lower grade. At the Last Chance prospect (Sainsbury, 1957, p. 156), a pegmatite body 2 to 3 feet thick contains thin books of silvery mica up to 1.5 inches in diameter. The estimated mica content of the pegmatite is less than 10%. The prospect was explored by a 4-foot-long trench.

Economic information about the deposit and operations

Development status Prospect
Commodity type Non-metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Hyder

Comments on the workings information

  • Workings / Exploration = The Hyder Mica prospect was explored, probably in the 1950s, by five trenches up to 40 feet long, and by several pits. Some of the mica was classified by federal and state agencies as 'strategic grade muscovite mica,' but most of the mica was of lower grade. The Last Chance prospect was explored by a four-foot trench.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Sainsbury, 1957

General comments

Subject category Comment text
Deposit Other Comments = The site is in Wilderness of the Misty Fiords National Monument.

Reporter information

Type Date Name Affiliation Comment
Reporter 03-FEB-1999 H.C. Berg U.S. Geological Survey

Beyond USGS

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

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.