Unnamed Occurrence (ARDF - MM088; East Fork of Glen Creek), Kantishna Mining District, Denali Borough, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - MM088; East Fork of Glen Creek)	- not defined -
Kantishna Mining District	Mining District
Denali Borough	Borough
Alaska	State
USA	Country

The boulder deposits and their presumed bedrock source are in Denali National Park and Preserve.
Location: This is an inferred location for a proximate bedrock source of rhodonite boulders that have long been known to occur in Glen Creek (MM108). The location of the boulders is in the East Fork of Glen Creek about a half-mile above its confluence with the West Fork. It is somewhat upstream of occurrence 76 of Thornsberry, McKee, and Salisbury (1984), cited as a rhodonite boulder locality, but seems to agree more closely with their text description of the locality.
Geology: Manganiferous boulders have long been known in Glen Creek. The boulders contain rhodonite and rhodochrosite, and are stained with a black oxide, probably pyrolusite. An early-reported location of the boulders is on socalled Claim No. 9, where black-stained pebbles and small boulders of rhodonite accompanied placer gold and galena (Capps, 1919, p. 84). It is not certain whether this claim is in the East Fork or in Glen Creek below the junction of the two forks. Rhodonite on Glen Creek was also reported by Wells (1933, p. 355-356; p. 372); and Bundtzen, Smith, and Tosdal (1976, p. 9) reported that some of the rhodonite in Glen Creek is of gem quality. The country rock near the boulder locality consists partly of marble of the Spruce Creek sequence, a possible host for replacement(?) deposits of manganese minerals.
Workings: The manganiferous boulders may have been discovered in 1916, when they were reported in sluice box concentrate on Claim No. 9 (Capps, 1919). They were also noted in 1931 (Wells, 1933), and in recent mining operations (Bundtzen, Smith, and Tosdal, 1976; Thornsberry, McKee, and Salisbury, 1984).
Age: The boulder deposit is Holocene.
Alteration: Oxidation of manganese mineral.
Production: Small amounts of the rhodonite have probably been sold as gem material.

Commodities (Major) - Rhodonite (as a gem mineral, not as an ore o; (Minor) - Mn
Development Status: None

Other Databases

Link to USGS - Alaska:	MM088

Other Regions, Features and Areas containing this locality

References