Ruby Creek Occurrence, Southeast Fairbanks Census Area, Alaska, USA i
Regional Level Types
Ruby Creek Occurrence Occurrence
Southeast Fairbanks Census Area Census Area
Alaska State
USA Country

Location: Ruby Creek is a 10-mile-long wesy tributary of Slate Creek. The occurrence is located near the mouth of Ruby Creek, in section 29, T. 3 S., R. 25 E., of the Fairbanks Meridian. The location is accurate within one-half mile. Ruby Creek is locality 41 of Cobb (1972 [MF-393]).
Geology: The rocks in the vicinity of Ruby Creek are granitic rocks of probable Mesozoic age, Tertiary felsic igneous rocks, and Paleozoic schist, greenschist, quartzite, and marble (Foster, 1976). Biotite from the Ruby Creek granite gives a 40Ar/39Ar plateau age of 102.1 +/- 0.4 Ma (Newberry and others, 1996). Monazite and allanite were found in heavy-mineral concentrates at the mouth of Ruby Creek in 1949 during a reconnaissance for radioactive deposits (Wedow and others, 1954). The source of the monazite and allanite is presumably granitic rocks in the drainage.
Workings: Monazite and allanite were found in heavy mineral concentrates at the mouth of Ruby Creek in 1949 during a reconnaissance for radioactive deposits (Wedow and others, 1954).

Commodities (Major) - REE, Th
Development Status: None

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.

ⓘ Rare Earths

ⓘ Thorium

Mineral List

ⓘ 'Allanite Group'

ⓘ 'Monazite Group'

Detailed Mineral List:

ⓘ 'Allanite Group'

Formula: (A1²⁺REE³⁺)(M1³⁺M2³⁺M3²⁺)O[Si₂O₇][SiO₄](OH)

References:

(2008) Alaska Resource Data File (ARDF) Open-File Report 2008-1225. US Geological Survey

ⓘ 'Monazite Group'

Formula: REE(PO₄)

References:

(2008) Alaska Resource Data File (ARDF) Open-File Report 2008-1225. US Geological Survey

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Unclassified
ⓘ	'Monazite Group'	-	REE(PO₄)
ⓘ	'Allanite Group'	-	(A1²⁺REE³⁺)(M1³⁺M2³⁺M3²⁺)O[Si₂O₇][SiO₄](OH)

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Allanite Group	(A1²⁺REE³⁺)(M1³⁺M2³⁺M3²⁺)O[Si₂O₇][SiO₄](OH)
O	Oxygen
O	ⓘ Monazite Group	REE(PO₄)
O	ⓘ Allanite Group	(A1²⁺REE³⁺)(M1³⁺M2³⁺M3²⁺)O[Si₂O₇][SiO₄](OH)
Si	Silicon
Si	ⓘ Allanite Group	(A1²⁺REE³⁺)(M1³⁺M2³⁺M3²⁺)O[Si₂O₇][SiO₄](OH)
P	Phosphorus
P	ⓘ Monazite Group	REE(PO₄)

Other Databases

Link to USGS - Alaska:	EA039

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Yukon-TananaVolcanic Arc
Yukon-Tanana upper DomainDomain

USA

Alaska
- Fortymile Mining DistrictMining District

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References

Cobb, E.H., 1972, Metallic mineral resources map of the Eagle quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-393, 1:250,000 scale, 1 sheet. Cobb, E.H., 1977, Summary of references to mineral occurrences in the Eagle quadrangle, Alaska: U.S. Geological Survey Open-File Report 77-845, 122 p. Newberry, R.J., Layer, P.W., Burleigh, R.E., and Solie, D.N., 1996, New 40Ar/39Ar dates for intrusions and mineral prospects in the eastern Yukon-Tanana terrane, Alaska - Regional patterns and significance, in Gray, J.E., and Riehle, J.R., eds., Geological Studies in Alaska by the U.S. Geological Survey, 1996: U.S. Geological Survey Professional Paper 1595, p. 131-159. Wedow, Helmuth, Jr., and White, M.G., 1954, Reconnaissance for radioactive deposits in east-central Alaska, 1949: U.S. Geological Survey Circular 335, 22 p.

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