mineral

Psilomelane (Manganese Ore)

Psilomelane (Ba,H2O)2Mn5O10

Hardness: 5.0–6.0. Color: Iron-black to dark steel-gray. Luster: Submetallic to dull/earthy. Crystal structure: Monoclinic (usually occurs in massive, botryoidal, or stalactitic forms). Clear black streak.

Hardness: 5
Color: Iron-black to dark steel-gray
Luster: Submetallic to dull/earthy

Identified March 20, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Secondary mineral formed in the oxidation zones of manganese deposits or through groundwater precipitation in sedimentary environments. Often found as a coating or within weathered lacustrine and bog deposits.

Uses & applications

Primarily used as an ore of manganese for the production of steel and other alloys. In jewelry, high-quality botryoidal specimens or 'Merlinite' variants are polished into cabochons for collectors.

Geological facts

Also known as 'Black Hematite' (though inaccurate) and 'Crown of Silver.' It often forms distinctive 'grape-like' (botryoidal) clusters and is frequently associated with other manganese minerals like Pyrolusite and Hausmannite.

Field identification & locations

Identify in the field by its high specific gravity, deep black streak on porcelain, and characteristic botryoidal or dendoritic 'mossy' growth patterns. Frequently found in Germany, UK, and the USA (Appalachian Mountains).

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral