Dyckman

The Dyckman is a zinc, arsenic, and molybdenum mine located in Alaska.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Dyckman

Commodity

Primary: Zinc
Primary: Arsenic
Primary: Molybdenum
Secondary: Gold

Location

State: Alaska
District: McGrath

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Occurrence
Operation Type: Unknown
Years of Production:
Organization:
Significant:

Physiography

Not available

Mineral Deposit Model

Not available

Orebody

Not available

Structure

Not available

Alterations

Alteration Type: L
Alteration Text: Intensive clay alteration of feldspars; chalcedonic replacements in rhyolitic breccias.

Rocks

Not available

Analytical Data

Not available

Materials

Ore: Sphalerite
Ore: Arsenopyrite
Gangue: Hematite

Comments

Comment (Geology): Geologic Description = The Dyckman occurrence consists of disseminated arsenopyrite in an intensively altered, rhyolite volcanic (?) breccia. Extensive clay alteration has completely altered all feldspar minerals. The alteration zone was traceable for nearly 500 feet (152 m) along strike. The width of the zone is unknown. The mineral occurrence is inferred to be Cretaceous, based on isotopic age of host rhyolite (Moll and others, 1981). Two grab samples contained 350 ppm zinc and 234 ppm arsenic (Clautice and others, 1993). One sample contained 9 ppb gold (Clautice and others, 1993). DiMarchi and others (1992) report values of 1,630 ppm molybdenum and 574 ppm arsenic from limonitically stained zones in rhyolitic breccia on Dyckman Mountain.

Comment (Exploration): Status = Inactive

Comment (Reference): Primary Reference = Clautice and others, 1993

Comment (Workings): Workings / Exploration = Two grab samples contained 350 ppm zinc and 234 ppm arsenic (Clautice and others, 1993). One sample contained 9 ppb gold (Clautice and others, 1993). DiMarchi and others (1992) report values of 1,630 ppm molybdenum and 574 ppm arsenic from limonitically stained zones in rhyolitic breccia on Dyckman Mountain.

Comment (Geology): Age = Inferred to be Cretaceous, based on isotopic age of host rhyolite (Moll and others, 1981).

References

Reference (Deposit): DiMarchi, J.J., Weglarz, T.B., Freeman, L.K., Nicholson, L.C., and Barker, J.C., 1992, Annual Report for 1992--Doyon Option Lands, Block 10: ASA Inc. Report, 121 pages (Report held by Doyon Ltd., Fairbanks, Alaska.)

Reference (Deposit): Clautice, K.H., Bowman, N.D., Clough, J.G., Gilbert, W.G., Kline, J.T., Smith, T.E., and Blodgett, R.B., 1993, Land selection Unit 8 (Kantishna River, Ruby, and Medfra quadrangles): References, lead isotope, geochemical and major oxide data: Alaska Division of Geological and Geophysical Surveys, 42 p., 1 sheet, scale 1:250,000.

Reference (Deposit): Moll, E.J., Silberman, M.L., and Patton, W.W. Jr., 1981, Chemistry, mineralogy, and K-Ar ages of igneous and metamorphic rocks of the Medfra quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-811C, 15 p., 2 sheets, scale 1:250,000.

The Top Ten Gold Producing States

These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.