About Siderite

FeCO₃

Iron carbonate of the calcite group, usually brown to yellowish brown, recognised by its rhombohedral cleavage, relatively high density for a carbonate and frequently curved rhombohedral crystals.

Show 25 localities on the map

Photos of Siderite

**Siderite** · 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

**Siderite** · Neudorf (Harzgerode)
Siderite with dolomite from Neudorf, Harz (field of view 6 cm).
Photo: Leon Hupperichs · CC BY-SA 3.0 · Source

**Siderite** · Sir James Mine (Sir James Pit)
Siderite-hematite-quartz banded iron formation at the abandoned Sir James Pit near Wawa, Ontario (photo 1 of a series).
Photo: James St. John · CC BY 2.0 · Source

**Siderite** · Aggeneys
Plate of gemmy, doubly terminated siderite crystals with chalcopyrite on matrix from Aggeneys.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source

**Siderite** · Mont Saint-Hilaire
Sharp deep-olive siderite rhomb with a smaller rhomb on its corner, Mont Saint-Hilaire.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source

**Siderite** · Baia Sprie Mine (Felsobanya)
Waxy honey-brown botryoidal sphaerosiderite on a sulfide crust from the Baia Sprie Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source

**Siderite** · Panasqueira Mine
Single fan-shaped, gemmy siderite blade from Panasqueira.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source

**Siderite** · Moscow (Latah County)
Nest of lustrous black sphaerosiderite balls in a vug, Moscow, Idaho.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source

Where Siderite is found (25)

Bolivia

Siglo Veinte MinePotosi · 1 photo
Tazna Mine (Tasna)Potosi · 2 photos

Brazil

Morro Velho MineMinas Gerais · 5 photos

Canada

Mont Saint-HilaireQuebec · 5 photos
Sir James Mine (Sir James Pit)Ontario · 5 photos

France

AllevardIsere · 1 photo

Germany

Farmsen clay pit (Farmser Tonkuhle)Lower Saxony · 2 photos
Georg Mine (Willroth)Rhineland-Palatinate · 1 photo
Neudorf (Harzgerode)Saxony-Anhalt · 5 photos

Italy

TraversellaPiemonte · 1 photo

Kosovo

Trepca complexMitrovica District · 2 photos

Mexico

Santa Eulalia Mining DistrictChihuahua · 2 photos

Namibia

Tsumeb MineOshikoto Region · 2 photos

Portugal

Panasqueira MineCastelo Branco District · 3 photos

Romania

Baia Sprie Mine (Felsobanya)Maramures County · 4 photos

Russia

Bor Pit (Dal'negorsk B deposit)Primorsky Krai · 1 photo
DalnegorskPrimorsky Krai · 1 photo
Nikolaevskiy MinePrimorsky Krai · 2 photos

South Africa

AggeneysNorthern Cape · 5 photos

United Kingdom

Camborne-Redruth-St Day DistrictCornwall · 1 photo

United States

Bisbee (Warren Mining District)Arizona · 2 photos
Hiddenite (Alexander County)North Carolina · 2 photos
Lovilia area (Monroe County)Iowa · 2 photos
Moscow (Latah County)Idaho · 3 photos
Roxbury Iron Mine (Mine Hill)Connecticut · 3 photos

Siderite on the same specimen with other minerals

Same specimen Siderite with Chalcopyrite at Neudorf (Harzgerode)

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

Same specimen Siderite with Galena at Neudorf (Harzgerode)

1 specimen photo(s) from this locality show galena with siderite 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 Siderite at Aggeneys

1 specimen photo(s) from this locality show siderite 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 Sphalerite with Siderite at Aggeneys

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

Same specimen Dolomite with Siderite at Morro Velho Mine

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 at Morro Velho Mine

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 Dolomite with Siderite at Neudorf (Harzgerode)

Same specimen Galena with Siderite at Neudorf (Harzgerode)

2 specimen photo(s) from this locality show siderite with galena 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 Siderite at Neudorf (Harzgerode)

3 specimen photo(s) from this locality show siderite 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 Sphalerite with Siderite at Neudorf (Harzgerode)

1 specimen photo(s) from this locality show siderite with sphalerite 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 Siderite at Trepca complex

2 specimen photo(s) from this locality show siderite 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 Siderite at Santa Eulalia Mining District

1 specimen photo(s) from this locality show siderite 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 Barite with Siderite at Baia Sprie Mine (Felsobanya)

1 specimen photo(s) from this locality show siderite with barite 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 at Baia Sprie Mine (Felsobanya)

Same specimen Calcite with Siderite at Nikolaevskiy Mine

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

Same specimen Calcite with Siderite at Lovilia area (Monroe County)

Same specimen Pyrite with Siderite at Siglo Veinte Mine

1 specimen photo(s) from this locality show siderite 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 Siderite at Allevard

Same specimen Quartz with Siderite at Camborne-Redruth-St Day District

Same specimen Quartz with Siderite at Georg Mine (Willroth)

Same specimen Siderite with Pyrrhotite at Santa Eulalia Mining District

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

Identity

Also called: chalybite; iron spar; spathose iron
Group: Calcite Group
Strunz: 5.AB.05 · 5 Carbonates and nitrates
Name origin: From Greek 'sideros' (iron), for the iron in its composition.
Elements: Fe, C, O

Physical properties

Color: Yellowish brown to brown; also white, ash-gray, yellowish gray or pale green
Streak: White
Luster: Vitreous luster
Transparency: Translucent
Mohs hardness: 3.75–4.25
Density: 3.93–3.96 g/cm³
Cleavage / fracture: Perfect rhombohedral cleavage on {10-11}; fracture uneven to conchoidal; brittle
Magnetism / fluorescence: Not fluorescent

Crystallography

Crystal system: Trigonal
Space group: R-3c
Structure: Calcite-type carbonate structure (calcite group, space group R-3c) with Fe2+ in the cation site.
Typical habit: Rhombohedra, often with curved (saddle-shaped) faces, steep scalenohedra, prisms and tablets; also fibrous, stalactitic, spherulitic (sphaerosiderite), cleavable and fine-grained massive
Twinning: Uncommon, lamellar on {01-12}; rare on {0001}
Optical data: Uniaxial (-); omega = 1.875, epsilon = 1.633; very high birefringence; strong dispersion

Formation and use

Formation: Bedded sedimentary iron ores and metamorphic iron formations; hydrothermal metal veins; rarely granite and nepheline syenite pegmatites; carbonatites; authigenic and in concretions.
Uses: Iron ore, for example the spathic iron ores of the Wied district (Germany) and the siderite iron formation of the Michipicoten range (Ontario); collector specimens.

Related minerals

Related minerals: Magnesiterhodochrositesmithsonitecalcite

Sources

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
SRC-587 · Database
Siderite Mineral DataBarthelmy, D. · Webmineral.com
SRC-588 · Database
Sir James Dunn Mine (MDI42C02SE00013), Ontario Mineral InventoryOntario Geological Survey · Ontario Ministry of Mines - GeologyOntario
SRC-599 · Website
Grube GeorgWikipedia contributors · Wikipedia (German)

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.