Vote for your favorite mineral in #MinCup26! - Cuprite vs. Orpiment
It's a fiery match of vibrant red Cuprite and just as saturated orange Orpiment battle for your votes!
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

McCaskey Bar Mine, Hot Springs Mining District, Yukon-Koyukuk Census Area, Alaska, USAi
Regional Level Types
McCaskey Bar MineMine
Hot Springs Mining DistrictMining District
Yukon-Koyukuk Census AreaCensus Area
AlaskaState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearch
Latitude & Longitude (WGS84):
65° 10' 3'' North , 150° 12' 46'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Mindat Locality ID:
198804
Long-form identifier:
mindat:1:2:198804:1
GUID (UUID V4):
0


Location: McCaskey Bar is a bench between Eureka and Kentucky Creeks. The site is at the mine symbol on the east side of Eureka Creek, in the southwest quarter of section 16, T. 4 N., R. 13 W., of the Fairbanks Meridian. According to Cobb (1972, location 42; 1977), the area of placer mining extends eastward from the mine symbol for about a mile. The western edge of the placer mine is apparently within a quarter mile of a landing strip to the northwest. The location is accurate within half a mile. This site is approximately 0.5 mile west of the site for McCaskey Bar, U.S. Bureau of Land Management MAS number 0020480048.
Geology: Bedrock in the area of the McCaskey Bar placer deposit consists of Jurassic or Cretaceous clastic sedimentary strata that are cut by thrust faults and locally intruded by one or more dikes of unknown composition (Chapman and others, 1982; Reifenstuhl and others, 1998). Mertie (1934) described the bedrock in the mined area as altered phyllite and argillite, often so decomposed that no hard rock could be found. A dike that cuts the country rock is just as altered, and quartz veins in the bedrock are also decomposed and iron-stained. Mertie (1934) described McCaskey Bar as an old terrace placer east of Eureka Creek, approximately 250 feet above the active stream channel. The gold appears to be concentrated in the upper foot or so of the bedrock, but minor amounts also occur throughout the gravels in streaks at least 100 feet wide. Mertie reported the fineness of gold in one sample as 802.75. The largest nugget reported as of 1931 was worth $8.00 (gold at $20.67 per ounce). The heavy mineral concentrates contained ilmenite, picotite, cinnabar, and magnetite (Waters, 1934). Mining has been mainly by hydraulicking the frozen overburden and allowing the ground to thaw naturally. Water is scarce in summer and mining was intermittent (Mertie, 1934). Cobb's (1977) and Smith's (1933) reports of Farmer & Jones operating a hydraulic mine in 1928 in the Eureka Creek area actually refer to an operation on McCaskey Bar (Wimmler, 1926). Ray C. Pittman operated a bulldozer just south of McCaskey Bar on Eureka Creek in 1975 (Carnes, 1976).
Workings: McCaskey Bar was mined by hydraulic methods and sluicing starting in 1924 and continued through the 1930's (Mertie, 1934). Cobb's (1977) and Smith's (1933) reports of Farmer & Jones operating a hydraulic mine in 1928 in the Eureka Creek area actually refer to an operation on McCaskey Bar (Wimmler, 1926, 1930). Ray C. Pittman operated a bulldozer just south of McCaskey Bar on Eureka Creek in 1975 (Carnes, 1976).
Age: Quaternary.
Production: No official records of production from McCaskey Bar have been made public.

Commodities (Major) - Au; (Minor) - Hg
Development Status: Yes; small
Deposit Model: Placer Au (Cox and Singer, 1986; model 39a).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


4 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Cinnabar2.CD.15aHgS
Group 4 - Oxides and Hydroxides
Magnetite4.BB.05Fe2+Fe3+2O4
Ilmenite4.CB.05Fe2+TiO3

List of minerals for each chemical element

OOxygen
O IlmeniteFe2+TiO3
O MagnetiteFe2+Fe23+O4
SSulfur
S CinnabarHgS
TiTitanium
Ti IlmeniteFe2+TiO3
FeIron
Fe IlmeniteFe2+TiO3
Fe MagnetiteFe2+Fe23+O4
AuGold
Au Native GoldAu
HgMercury
Hg CinnabarHgS

Other Databases

Link to USGS - Alaska:TN131

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Bottge, R.G., 1986, Maps summarizing land availability for mineral exploration and development in northcentral Alaska, 1985: U.S. Bureau of Mines Open-File Report 70-86, 14 sheets. Bundtzen, T.K., Swainbank, R.C., Deagen, J.R., Moore, J.L., 1990, Alaska's Mineral Industry 1989: Alaska Division of Geological & Geophysical Surveys, Special Report 44, 100 p. Carnes, D.R., 1976, Active Alaskan placer operations, 1975: U.S. Bureau of Mines Open-File Report 98-76, 90 p., 40 plates, scale 1:250,000. Chapman, R.M., Yeend, W.E., Brosge, W.P., and Reiser, H.N., 1982, Reconnaissance geologic map of the Tanana quadrangle: U.S. Geological Survey Open-File Report 82-734, 20 p., scale 1:250,000. Cobb, E.H., 1972, Metallic mineral resources map of the Tanana quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-371, 1 sheet, scale 1:250,000. Cobb, E.H., 1977, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Tanana quadrangle, Alaska: U.S. Geological Survey Open-File Report 77-432, 98 p. Mertie, J.B., Jr., 1934, Mineral deposits of the Rampart and Hot Springs districts, Alaska: U.S. Geological Survey Bulletin 844-D, p. 163-226. Reifenstuhl, R.R., Dover, J.H., Newberry, R.J., Clautice, K.H., Pinney, D.S., Liss, S.A., Blodgett, R.B., and Weber, F.R., 1998, Geologic map of the Tanana A-1 and A-2 quadrangles, central Alaska: Alaska Division of Geological and Geophysical Surveys Public Data File 98-37a, 19 p., 1 sheet, scale 1:63,360. Smith, P.S., 1933, Mineral industry of Alaska in 1931: U.S. Geological Survey Bulletin 844-A, p. 1-81. Waters, A.E., 1934, Placer concentrates of the Rampart and Hot Springs district: U.S. Geological Survey Bulletin 844-D, p. 163-246. Wimmler, N.L., 1926, Placer mining in Alaska in 1926: Alaska Territorial Department of Mines Miscellaneous Report 195-11, 121 p.
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 5, 2026 11:43:46 Page updated: August 29, 2025 06:42:53
Go to top of page