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Lustrous Manganite Crystal Grouping
OXIDES; HYDROXIDES · MONOCLINIC

Manganite

MnO(OH)

Hardness
3.5–4
Streak
Reddish brown to black
Spec. Gravity
4.3–4.4
System
Monoclinic

About

Manganite is a mineral named for its dominating manganese content. It forms in manganese deposits, where it is more common than perceived as an uninteresting mineral. However, several localities produce very aesthetic, well-crystallized forms of Manganite that are highly lustrous. These exceptional examples, especially those from Ilfied in Germany, are rarities that are highly prized by collectors, with high-end collectors vying for the top specimens of this mineral. 

Crystal Forms & Aggregates

Striking Features

Crystal habit, mode of occurrence, and streak

Environment

In low temperature hydrothermal replacement deposits, acid-rich bogs, and in manganese-rich hot springs.

Polymorphs

Uses

Manganite has been used as an ore of manganese in the past. The classic, well-crystallized forms of Manganite from Germany make an important collector's mineral that is highly prized by collectors.

Noteworthy Localities

The premier locality for Manganite is Ilfeld, in the Harz Mountains, Thuringia, Germany, where it was found in exceptionally lustrous blocky crystals. The best of this seems to have come from the late 1800's, with no new recent discoveries of interest.
Large and often curved crystals are found in the Kalahari manganese field, in Northern Cape Province, South Africa - at the Wessels Mine in Hotazel; and at the N'Chwaning Mines in Kuruman. Radiating and fibrous Manganite, resembling Pyrolusite, has come from the Bölet Manganese Mines, Undenäs, Karlsborg, Sweden.
Lustrous blocky Manganite crystals in vugs, as well as sharp acicular crystals, have been mined in Canada at the Caland Mine, Atikokan, in the Rainy River District, Ontario. Also in Canada is Walton and Cheverie, Hants Co., Nova Scotia, which has produced fibrous crystal groupings. The historic Michigan iron-mining districts of Negaunee, in the Marquette iron range, Marquette Co.; and Ironwood, in the Gogebic iron range, Gogebic Co. have also produced Manganite specimens of interest.

Common Mineral Associations

Distinguishing Similar Minerals

Pyrolusite - Rarely forms in large crystals like Manganite; otherwise can be distinguished by streak.Enargite - Luster is more metallic, and has a different streak.Goethite - Greater hardness, more brown in color color, and has a different streak.Hematite - Different crystal habits, greater hardness, more metallic luster.

Photos

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Crystal forms

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Elongated
Prismatic
Contact Twin