Mineral

Manganese Ore (Psilomelane/Pyrolusite)

Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)

Hardness: 5 to 6 on Mohs scale; Color: Black, dark gray, or bluish-black; Luster: Submetallic to dull; Crystal structure: Monoclinic or Orthorhombic (often occurs in massive or botryoidal forms); Specific Gravity: 4.4 to 4.7.

Hardness: 5 to 6 on Mohs scale
Color: Black, dark gray, or bluish-black
Luster: Submetallic to dull

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed as a secondary mineral in the oxidation zones of manganese deposits or as a chemical precipitate in sedimentary basins. Often found in hydrothermal veins and marine sedimentary environments through Precambrian to Cenozoic eras.

Uses & applications

Primary source of manganese for steel production (acting as a deoxidizer); used in dry cell batteries, pigment manufacturing, glassmaking to remove green tints, and chemical catalysts.

Geological facts

Manganese is the 12th most abundant element in the Earth's crust. Historically, Cave painters used ground manganese oxide as one of the first black pigments. Large quantities are often found at the bottom of the ocean in the form of 'manganese nodules'.

Field identification & locations

Identify in the field by its distinctive black streak on porcelain, heavy feel for its size, and typical soot-like residue when rubbed. Frequently found in arid regions like South Africa, Australia, and Brazil, or near ancient lake beds.

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