Manganolangbeinite

K2Mn2+2(SO4)3
IMA status
  • Approved
  • Grandfathered
IMA symbol
Mlgb
Discovered
1924
Also known as
  • Manganolangbeiniet

Where it forms, where it's found

Geological setting

In a volcanic cavern.

Type locality
Mount Vesuvius
  1. Metropolitan City of Naples
  2. Campania
  3. Italy

Physical

Hardness
123456789102.5 – 3/ 10 MOHS
  1. 1Talc
  2. 2Gypsum
  3. 3Calcite
  4. 4Fluorite
  5. 5Apatite
  6. 6Orthoclase
  7. 7Quartz
  8. 8Topaz
  9. 9Corundum
  10. 10Diamond
Colour
Rose-red
Density
3.02 g/cm³

Optical

Optical type
Isotropic
Isotropy testPPL ↔ XPL diagnostic
PPL intrinsic colour; no change on stage rotation
XPL extinct at every orientation

Crystallography

Crystal system
Isometric
Space group
#198
Cell parameters
a = 10.11 Å
Morphology

Small tetrahedra; artificial crystals exhibit (210) and (211).

Crystal structure

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
8OOxygenOxygen1215.999191.988
40.31%
25MnManganeseManganese254.938109.876
23.07%
16SSulfurSulfur332.06096.180
20.20%
19KPotassiumPotassium239.09878.196
16.42%
Total476.240100.00%

Mass share = atoms × atomic mass ÷ molar mass × 100

From IMA formula

Synonyms

  • Manganolangbeiniet

In other languages

German
Manganolangbeinit
Italian
Manganolangbeinite

Classification

Strunz
10th ed.

7.AC.10

  • 7SulfatesClass
  • 7.ASulfates (selenates, etc.) without additional anions, without H2ODivision
  • 7.ACWith medium-sized and large cationsGroup
  • 7.AC.10ManganolangbeiniteSpecies
Dana
8th ed.

28.04.04.02

  • 28Anhydrous Acid and Normal SulfatesClass
  • 28.04MiscellaneousType
  • 28.04.04Langbeinite SeriesGroup
  • 28.04.04.02ManganolangbeiniteSpecies
CIM

25.9.4

  • 25SulphatesClass
  • 25.9Sulphates of MnGroup
  • 25.9.4ManganolangbeiniteSpecies

Group, growth & confusion

In the same group
4 members

Literature, links & citation

Citations
  1. 1924Zambonini and Carobbi (1924) Reale accademia delle scienze fisische e matematiche, Naples, Rendus: (3): 30: 123.
  2. 1926American Mineralogist (1926): 11: 107.
  3. 1947Bellanca (1947) Reale accademia nazionale dei Lincei, Rome, Att., Cl. sc. (8): 2: 451.
  4. 1951Palache, Charles; Berman, Harry; Frondel, Clifford (1951) The System of Mineralogy (7th ed.) Vol. 2 - Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. John Wiley and Sons.
  5. 2007(2007) Manganolangbeinite. Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Manganolangbeinite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/manganolangbeinite-2485},
  note      = {Accessed 2026-05-11}
}