Provenite

Morro Velho Mine

MineUnknownDraft data

19.5900° S, 43.5100° W · ± 10 km

Pyrrhotite and Siderite from Minas Gerais, Brazil, with photos of specimens from this locality.

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Minerals found here

PyrrhotiteSiderite

On the same specimen

Same specimen Dolomite with Siderite

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

Same specimen Pyrrhotite with Siderite

1 specimen photo(s) from this locality show siderite with pyrrhotite 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 Pyrrhotite

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

Pyrrhotite at Morro Velho Mine

Two intergrown bronzy pyrrhotite crystals with accent calcite from the Morro Velho Mine.
Two intergrown bronzy pyrrhotite crystals with accent calcite from the Morro Velho Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Quartz crystal with sparkling inclusions of thin pyrrhotite plates from the Morro Velho Mine.
Quartz crystal with sparkling inclusions of thin pyrrhotite plates from the Morro Velho Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
Fe₁₋ₓS (x = 0-0.17)
Morphology
Large intergrown crystals; paper-thin plates included in quartz
Typical size
Crystals to about 5 cm
Color / luster
Bronzy metallic
Associated minerals
Calcitequartzsideritecubanitedolomite
Availability
Scarce
History
The Handbook lists large crystals from this gold mine.

Sources: SRC-627 SRC-480 SRC-637

About Pyrrhotite →

Siderite at Morro Velho Mine

Gemmy, lustrous yellow-green to amber siderite rhombs and blades, often accompanied by dolomite and small pyrrhotite or cubanite crystals.

Cluster of gemmy, lustrous golden siderite rhombs from the Morro Velho Mine.
Cluster of gemmy, lustrous golden siderite rhombs from the Morro Velho Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Two sharp yellow-green siderite rhombs with stepped faces from Morro Velho.
Two sharp yellow-green siderite rhombs with stepped faces from Morro Velho.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Glassy yellow-green siderite blades with stepped growth faces from Morro Velho.
Glassy yellow-green siderite blades with stepped growth faces from Morro Velho.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Amber-yellow discoidal siderite crystals with colourless dolomite from Morro Velho.
Amber-yellow discoidal siderite crystals with colourless dolomite from Morro Velho.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Arborescent cluster of tan siderite discs edged with small pyrrhotite and cubanite crystals, Morro Velho.
Arborescent cluster of tan siderite discs edged with small pyrrhotite and cubanite crystals, Morro Velho.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
FeCO₃
Morphology
Flattened rhombs looking like blades or discs, often in arborescent clusters
Typical size
Crystals up to about 3 cm
Color / luster
Gemmy yellow-green, amber-yellow to tan; highly lustrous
Associated minerals
Dolomitepyrrhotitecubanite
Surface features
Stepped growth faces
Availability
Scarce
History
Classic specimens came from finds in the 1960s in this deep gold mine.

Sources: SRC-586 SRC-480 SRC-603

About Siderite →

Geology of the locality

Setting
Very deep underground gold mine near Nova Lima; workings now exceed 3,000 m below surface.
Region
Minas Gerais
Country
Brazil

Worked since 1725; owned by the Saint John d'el Rey Mining Company from 1834 and later operated by AngloGold Ashanti. Coordinates are the minute-level values of the Wikipedia article.

Sources: SRC-480

Sources

  1. SRC-480 · Website
    Morro VelhoWikipedia contributors · Wikipedia
  2. SRC-627 · Book
    Handbook of Mineralogy - PyrrhotiteAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2005 · Mineral Data Publishing / Mineralogical Society of America
  3. SRC-637 · Website
    File:Pyrrhotite-188146.jpgRobert M. Lavinsky · Wikimedia Commons
  4. SRC-586 · Book
    Handbook of Mineralogy - SideriteAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2005 · Mineral Data Publishing / Mineralogical Society of America
  5. SRC-603 · Website
    File:Siderite-Pyrrhotite-Cubanite-224106.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.