Location: Occurence is located in Sischu Creek valley at an approximate elevation of 1,000 feet (304 m) in Section 35, T. 17 S., R. 29 E., of the Kateel River Meridian. Location is imprecise and only known to within a one mile (1.6 km) radius.
Geology: Quartz-rhyolite porphyry was found to contain anomalous thorium and uranium. Ore minerals were not identified (Miller and others, 1980; Clautice and others, 1993). Mineralization is inferred to be Early Tertiary, based on isotopic ages from Sischu Volcanic Field (Moll and others, 1980). Miller and others (1980) report up to 16.5 ppm uranium, and 70.4 ppm thorium from grab samples.
Workings: Miller and others (1980) report up to 16.5 ppm U, and 70.4 ppm Th from grab samples.
Age: Inferred to be Early Tertiary, based on isotopic ages from Sischu Volcanic Field (Moll and others, 1980).
Reserves: None.

Commodities (Major) - Th, U
Development Status: No
Deposit Model: Volcanogenic Uranium (Cox and Singer, 1986; model no. 25f)

Commodity List

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

ⓘ Thorium

ⓘ Uranium

List of minerals for each chemical element

Other Databases

Link to USGS - Alaska:	MD001

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Farewell-McGrath DomainDomain
Farewell TerranePassive Margin

USA

Alaska
- Yukon-Koyukuk Census Area
  - McGrath Mining DistrictMining District

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

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. Miller, T.P., Moll, E.J., and Patton, W.W. Jr., 1980, Uranium and thorium rich volcanic rocks of the Sischu Creek area, Medfra quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-803, 9 p.

Quick NavTop Commodities Other Databases Other Regions References

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 01:46:36 Page updated: July 23, 2025 04:51:59

Go to top of page