Provenite

Butte Mining District

AreaUnknownDraft data

46.0200° N, 112.5100° W · ± 10 km

Bornite, Chalcopyrite, Enargite, Pyrite, Rhodochrosite and Sphalerite from Montana, United States, with photos of specimens from this locality.

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Minerals found here

BorniteChalcopyriteEnargitePyriteRhodochrositeSphalerite

On the same specimen

Same specimen Enargite with Sphalerite

2 specimen photo(s) from this locality show sphalerite with enargite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Bornite with Sphalerite

2 specimen photo(s) from this locality show sphalerite with bornite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Quartz with Enargite

1 specimen photo(s) from this locality show enargite with quartz together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Pyrite with Bornite

1 specimen photo(s) from this locality show bornite with pyrite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Quartz with Bornite

1 specimen photo(s) from this locality show bornite with quartz together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Quartz with Rhodochrosite

1 specimen photo(s) from this locality show rhodochrosite with quartz together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Bornite at Butte Mining District

Butte is cited by the Handbook of Mineralogy as an important locality for fine bornite crystals.

Cluster of sharp dodecahedral steel-gray bornite crystals on quartz from Butte.
Cluster of sharp dodecahedral steel-gray bornite crystals on quartz from Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Black bornite crystal of 3.1 cm among bright intergrown pyrite crystals from Butte.
Black bornite crystal of 3.1 cm among bright intergrown pyrite crystals from Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Lightly iridescent charcoal-gray bornite crystals among clear quartz crystals from Butte.
Lightly iridescent charcoal-gray bornite crystals among clear quartz crystals from Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
Cu₅FeS₄
Morphology
Sharp dodecahedral to pseudocubic crystals in clusters, on quartz or with pyrite
Typical size
Crystals typically 1-1.5 cm, rarely about 3 cm
Color / luster
Steel-gray to charcoal-gray, lustrous to lightly iridescent
Associated minerals
Quartzpyrite
Surface features
Crystal faces often look partly melted or rounded
Availability
Scarce
History
Old-time specimens from the underground Butte mines

Sources: SRC-664 SRC-677

About Bornite →

Chalcopyrite at Butte Mining District

Ore-grade chalcopyrite from a giant porphyry-plus-vein system in granite, dominant in the deep pyrite-chalcopyrite-bornite-tennantite zone and replaced by bornite in places.

Formula
CuFeS₂
Morphology
Disseminated grains replacing mafic minerals, and fill in quartz veins and breccia matrix (porphyry stage); vein fill in the Main Stage veins
Associated minerals
Pyritebornitetennantitechalcocitesphaleritegalenamagnetitequartz
History
Placer gold mining began in 1864 and copper became central after the early 1880s; underground Main Stage vein mining continued until 1955, when the Berkeley Pit opened, and the Continental porphyry pit followed in 1980.

Sources: SRC-035 SRC-036

About Chalcopyrite →

Enargite at Butte Mining District

Splendent black striated enargite prisms from Butte are the classic North American enargite and among the best known for the species.

Cluster of striated, jet-black enargite prisms from Butte, about 4.7 cm across.
Cluster of striated, jet-black enargite prisms from Butte, about 4.7 cm across.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Robust dark black enargite crystals with minor pyrite from Butte, about 7 cm across.
Robust dark black enargite crystals with minor pyrite from Butte, about 7 cm across.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Large group of lustrous enargite crystals with small pyrite and quartz crystals from Butte, about 9.5 cm across.
Large group of lustrous enargite crystals with small pyrite and quartz crystals from Butte, about 9.5 cm across.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Old Butte enargite cluster with shiny crystals over 2 cm long.
Old Butte enargite cluster with shiny crystals over 2 cm long.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Short prismatic gray enargite crystals on a druse of white quartz from Butte.
Short prismatic gray enargite crystals on a druse of white quartz from Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
Cu₃AsS₄
Morphology
Sharp, striated prismatic crystals in clusters, sometimes doubly terminated
Typical size
Crystals commonly 0.7-2 cm; clusters up to about 10 cm
Color / luster
Jet-black to battleship-gray with splendent metallic luster
Associated minerals
Pyritequartz
Surface features
Prism faces striated
Availability
Scarce
History
Old-time specimens from the underground Butte mines; the X-ray reference pattern of enargite in the Handbook of Mineralogy is from Butte.

Sources: SRC-642 SRC-652

About Enargite →

Pyrite at Butte Mining District

Classic old American pyrite from a porphyry copper district, with sharp modified octahedra often on quartz-lined matrix.

Brilliant modified octahedral pyrite crystals from the Butte district, Montana.
Brilliant modified octahedral pyrite crystals from the Butte district, Montana.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Old Butte pyrite specimen with sharp modified octahedra on a quartz-crystal-lined matrix.
Old Butte pyrite specimen with sharp modified octahedra on a quartz-crystal-lined matrix.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Knob of golden octahedral pyrite crystals from the Butte district, Montana.
Knob of golden octahedral pyrite crystals from the Butte district, Montana.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
FeS₂
Morphology
Octahedra and modified octahedra; pyritohedral clusters
Typical size
Crystals up to about 3 cm
Color / luster
Brass-yellow with mirror-bright metallic luster
Associated minerals
Quartzchalcopyrite
History
Specimens in collections date from the mid-twentieth century and earlier.

Sources: SRC-405 SRC-406

About Pyrite →

Rhodochrosite at Butte Mining District

A plate of pastel-pink rhodochrosite rhombs with needle quartz and sulfides on massive rhodochrosite, Butte.
A plate of pastel-pink rhodochrosite rhombs with needle quartz and sulfides on massive rhodochrosite, Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Sharp salmon-coloured rhodochrosite rhombs with silky luster from Butte, Montana.
Sharp salmon-coloured rhodochrosite rhombs with silky luster from Butte, Montana.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Rhodochrosite specimen about 6 cm long from the Butte district, Montana.
Rhodochrosite specimen about 6 cm long from the Butte district, Montana.
Photo: Leon Hupperichs · CC BY-SA 3.0 · Source
Sharp rose-red rhodochrosite rhombs to 2.2 cm with a rosette of quartz crystals, Butte.
Sharp rose-red rhodochrosite rhombs to 2.2 cm with a rosette of quartz crystals, Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Translucent rhodochrosite crystals on drusy quartz over sulfide matrix from the Lexington Mine, Walkerville, Butte.
Translucent rhodochrosite crystals on drusy quartz over sulfide matrix from the Lexington Mine, Walkerville, Butte.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
MnCO₃
Morphology
Sharp rhombs on massive rhodochrosite, with needle quartz and sulfides
Typical size
Rhombs to about 2.2 cm
Color / luster
Pastel-pink, salmon to rose-red; silky to lustrous
Associated minerals
Quartzsulfides
Availability
Scarce

Sources: SRC-891 SRC-892 SRC-893

About Rhodochrosite →

Sphalerite at Butte Mining District

Mounds of lustrous black sphalerite crystals lightly coated with iridescent bornite and topped with enargite clusters, from the Butte district.
Mounds of lustrous black sphalerite crystals lightly coated with iridescent bornite and topped with enargite clusters, from the Butte district.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Platy sphalerite dusted with iridescent bornite, with small enargite crystals and needle quartz, from the Butte district.
Platy sphalerite dusted with iridescent bornite, with small enargite crystals and needle quartz, from the Butte district.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
(Zn,Fe)S
Morphology
Platy to mound-like crystal aggregates
Color / luster
Black, lustrous, often with iridescent bornite coating
Associated minerals
Borniteenargitequartz
Availability
Unknown

Sources: SRC-374 SRC-385

About Sphalerite →

Geology of the locality

Setting
Porphyry copper-molybdenum system (about 66-61 Ma) overprinted by younger polymetallic Main Stage veins, in the Late Cretaceous Boulder Batholith.
Type
Hydrothermal
Host rock
Butte Granite (Boulder Batholith)
Region
Montana
Country
United States

District-level point taken from the Berkeley Pit coordinates on Wikipedia (SRC-036). The Berkeley Pit closed in 1982 (SRC-036); the Continental porphyry pit has been run by Montana Resources since 1986 according to SRC-035, and current status was not checked.

Sources: SRC-035 SRC-036

Sources

  1. SRC-035 · Article
    Ore Deposits of Butte, MontanaReed, M.; Dilles, J. · Montana Bureau of Mines and Geology (geology volume chapter)
  2. SRC-036 · Website
    Berkeley Pit (Wikipedia)Wikipedia
  3. SRC-664 · Book
    Handbook of Mineralogy - BorniteAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2005 · Mineral Data Publishing / Mineralogical Society of America
  4. SRC-677 · Website
    File:Bornite-162973.jpg; File:Bornite-Pyrite-66363.jpg; File:Bornite-Quartz-285100.jpg (Wikimedia Commons)Robert M. Lavinsky · Wikimedia Commons
  5. SRC-642 · Book
    Handbook of Mineralogy - EnargiteAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2005 · Mineral Data Publishing / Mineralogical Society of America
  6. SRC-652 · Website
    File:Enargite-118194.jpg; File:Enargite-280299.jpg; File:Enargite-Quartz-173234.jpg (Wikimedia Commons)Robert M. Lavinsky · Wikimedia Commons
  7. SRC-405 · Website
    Pyrite photographs and file descriptions on Wikimedia CommonsRobert M. Lavinsky (photographer; file descriptions) · Wikimedia Commons
  8. SRC-406 · Article
    Porphyry Cu-Mo stockwork formation by dynamic, transient hydrothermal pulses: Mineralogic insights from the deposit at Butte, MontanaMercer, C.N.; Reed, M.H. · 2013 · Economic Geology
  9. SRC-891 · Website
    File:Rhodochrosite-176305.jpgRobert M. Lavinsky · Wikimedia Commons (dealer label)
  10. SRC-892 · Website
    File:Rhodochrosite-41066.jpgRobert M. Lavinsky · Wikimedia Commons (dealer label)
  11. SRC-893 · Website
    File:Rhodochrosite-Quartz-119958.jpgRobert M. Lavinsky · Wikimedia Commons (dealer label)
  12. SRC-374 · Article
    Critical Minerals in Zinc Ore: An Update on Earth Mapping Resources Initiative Research in the Boulder Batholith Region, Montana (USGS Fact Sheet 2026-3064)Gaynor, S.P.; Anderson, E.D.; Eastman, K.A.; Lund, K.; Gammons, C.; Lowers, H.; Thompson, J. · 2026 · U.S. Geological Survey
  13. SRC-385 · Website
    Wikimedia Commons file page Sphalerite-Enargite-Bornite-261723.jpgRobert M. Lavinsky · 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.