psilomelane
Sign in to saveAlso known as manganomelane
Psilomelane is a group name for hard black manganese oxides including hollandite and romanechite. Psilomelane consists of hydrous manganese oxide with variable amounts of barium and potassium. Psilomelane is erroneously, and uncommonly, known as black hematite, despite not being related to true hematite, which is an iron oxide.
Key facts
- Mineral.name
- Psilomelane
- Mineral.category
- Oxide minerals
- Mineral.image
- Mineraly.sk - psilomelan.jpg
- Mineral.imagesize
- 260px
- Mineral.formula
- General formula:, or as Barium manganese oxide hydroxide
- Mineral.molweight
- 590.03 g/mol
- Mineral.system
- Monoclinic
- Mineral.color
- Black with gray pyrolusite bands
- Mineral.habit
- Botryoidal, mammillary, reniform
- Mineral.cleavage
- None
- Mineral.fracture
- Conchoidal and uneven
- Mineral.mohs
- 5.0 – 6.0
- Mineral.luster
- Sub-metallic, dull
- Mineral.polish
- Vitreous to subadamantine
- Mineral.streak
- Brownish black
- Mineral.gravity
- 3.7 – 4.7
- Mineral.solubility
- in hydrochloric acid
- Mineral.diaphaneity
- Opaque
via Wikipedia infobox
Wikidata facts
- Image
- Mineraly.sk - psilomelan.jpg
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- Commons category
- Psilomelane
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Article
6 sectionsContents
- Formula
- Characteristics
- History and occurrence
- Image gallery
- See also
- References
Psilomelane is a group name for hard black manganese oxides including hollandite and romanechite. Psilomelane consists of hydrous manganese oxide with variable amounts of barium and potassium. Psilomelane is erroneously, and uncommonly, known as black hematite, despite not being related to true hematite, which is an iron oxide.
==Formula== Generalized formula may be represented as or as . It is sometimes considered to be a hydrous manganese manganate, but of doubtful composition. The amount of manganese present corresponds to 70-80% of manganous oxide with 10-15% of available oxygen.