Provenite

Sunnyside Mine (American Tunnel)

MineClosedDraft data

37.9031° N, 107.6114° W · ± 1 km

Rhodochrosite from Colorado, United States, with photos of specimens from this locality.

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Minerals found here

Rhodochrosite

Rhodochrosite at Sunnyside Mine (American Tunnel)

Pink frosted rhodochrosite rhombs to 1.3 cm lining a mounded quartz matrix, Sunnyside Mine.
Pink frosted rhodochrosite rhombs to 1.3 cm lining a mounded quartz matrix, Sunnyside Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Two generations of rhodochrosite, glassy cherry-red crystals over earlier crystals, from the American Tunnel.
Two generations of rhodochrosite, glassy cherry-red crystals over earlier crystals, from the American Tunnel.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Large specimen of skeletal, cast-like rhodochrosite crystals from the Sunnyside Mine.
Large specimen of skeletal, cast-like rhodochrosite crystals from the Sunnyside Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
A cluster of lustrous rose-red rhodochrosite rhombs on a larger calcite-coated rhodochrosite cleavage from the Sunnyside Mine (American Tunnel).
A cluster of lustrous rose-red rhodochrosite rhombs on a larger calcite-coated rhodochrosite cleavage from the Sunnyside Mine (American Tunnel).
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Sharp powder-pink rhodochrosite crystals from the Sunnyside Mine, Silverton district, Colorado.
Sharp powder-pink rhodochrosite crystals from the Sunnyside Mine, Silverton district, Colorado.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
MnCO₃
Morphology
Rhombs lining quartz matrix; also skeletal, cast-like crystals
Typical size
Rhombs to about 1.3 cm on photographed specimens
Color / luster
Pink to cherry-red, lustrous to frosted
Associated minerals
Quartzcalcitefluoritegalenasphaleritechalcopyritepyrite
Availability
Scarce
History
Ore production through the American Tunnel ended in 1991

Sources: SRC-390 SRC-400

About Rhodochrosite →

Geology of the locality

Setting
Multi-generation fissure-filling veins tied to the Eureka graben, a volcanic collapse structure between the Silverton and Lake City calderas.
Type
Hydrothermal
Region
Colorado
Country
United States

Coordinates from the Mindat page for the Sunnyside Mine group (37 deg 54 min 11 s N, 107 deg 36 min 41 s W). Commons file labels place the specimens at Howardsville / Silverton district; Mindat lists the Sunnyside Mine group in the Eureka district. Ore production through the American Tunnel ended in 1991.

Sources: SRC-390

Sources

  1. SRC-390 · Database
    Sunnyside Mine group, Bonita Peak, Gladstone, Eureka Mining District, San Juan County, Colorado, USAMindat.org contributors · Mindat.org / Hudson Institute of Mineralogy
  2. SRC-400 · Website
    Wikimedia Commons: Rhodochrosite-170569.jpg (Sunnyside)Lavinsky, R.M. · Wikimedia Commons

Draft data from the Provenite workbook. Check entries against the cited sources before relying on them. Photos are open-licence images from Wikimedia Commons; the author and licence are given with each photo.