Climax-Sweet Home and Leadville Area Supergene System

Region West, Rocky Mountains
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Original focus area based on Climax-type systems around Climax-Sweet Home deposits. A 15 km buffer was drawn around these two deposits and the southwestern edge encompasses numerous Mn (and Fe) producers from the Leadville district. Mineralization in Leadville (late Eocene) tends to be older than that at Climax and Sweet Home (Oligocene), and the supergene enrichment in the Leadville area occurs in carbonate-hosted sulfide deposits. The shape of this focus area is an intersection of the original Climax-Sweet Home polygon along with the Central Colorado Mineral Belt carbonate-replacement focus area.
Identified resources Historical production of manganese and silver.
Production Manganese is associated with mineralization in the Leadville district. Approximately 3.5 to 4.0 million tons of manganiferous +/- silver ore produced between 1885 and 1939 (Hedges, 1940). Analyses of manganese-iron ore shipped from the Leadville district range from 17 to 34% Mn (Emmons and others, 1927).
Status Past mining.
Estimated resources Estimated Mn resources ~ 2 million tons of oxidized ore (10 to 25% Mn) + another 2 million tons of manganosiderite (14 to 20% Mn) (Hedges, 1940).
Geologic maps Tweto (1953), scale 14,400; Wallace and others (2005), scale 1:24,000; Widmann, Bartos, Madole and others (2004), scale 1:24,000; Widmann, Bartos, McCalpin and Jackson (2004), scale 1:24,000; Ruleman and others (2018), scale 1:24,000.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Supergene Mn associated with carbonate-replacement and associated veins in Leadville district.
Deposits Leadville district (MRDS dep_id: 10008106), numerous mines, especially in western portion of district.
Evidence from mineral occurrences MRDS; Hedges (1940).
Geochemical evidence No data.
Geophysical evidence No data.
Evidence from other sources Various geochemical samples and descriptions in Emmons and others (1927). Leadville mineralization in general described in Thompson and Arehart (1990) and related publications.
Cover thickness and description Leadville orebodies occur within carbonate units within a few hundred meters of the surface. Supergene/oxidized ores variably located near numerous faults and fractures in district, and are therefore variably covered (for example, Emmons and others, 1927).
Authors Joshua M. Rosera.
New data needs More detailed aeromagnetic data in areas near large gravity lows would help locate altered areas that are smaller than Climax itself.
Geologic mapping and modeling needs 1:24,000 scale exist for most of this area.
Geophysical survey and modeling needs Rank 1 geophysical surveys may assist with delineating altered areas.
Digital elevation data needs Lidar is adequate.