Breunnerite

Where it forms, where it's found

100recorded occurrences

Source · OpenStreetMap

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
26FeIron Iron 1 55.845 55.845
39.84%
8OOxygen Oxygen 3 15.999 47.997
34.25%
12MgMagnesium Magnesium 1 24.305 24.305
17.34%
6CCarbon Carbon 1 12.011 12.011
8.57%
Total 140.158 100.00%
Mass share = atoms × atomic mass ÷ molar mass × 100
From Mindat formula

Mass composition breakdown
Element	Atoms	At. mass g/mol	Mass g/mol	Mass share
26FeIron	Iron	1	55.845	55.845	39.84%
8OOxygen	Oxygen	3	15.999	47.997	34.25%
12MgMagnesium	Magnesium	1	24.305	24.305	17.34%
6CCarbon	Carbon	1	12.011	12.011	8.57%
	Total	140.158	100.00%

Synonyms

Breinnerite
Breunerite
Breunnerit
Breunnerita

Literature, links & citation

Citations

1825Mohs, Frederick; Haidinger, William (1825) Treatise on Mineralogy Vol. 1.
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.
2016www.mineralienatlas.de (n.d.) https://www.mineralienatlas.de/lexikon/index.php/Breunner,%20August%20Graf?lang=en&language=english
2025Mitchell, Roger H. (2025) Recommendations for the Terminology of Carbonates in the Ternary System CaCO3–MgCO3–FeCO3 with Reference to Ankerite, “Breunnerite”, the Magnesite–Siderite Solid Solution Series, and Carbonatite Nomenclature. The Canadian Journal of Mineralogy and Petrology, 63 (4). 319-323 doi:10.3749/2500029DOI: 10.3749/2500029

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Breunnerite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/breunnerite-7873},
  note      = {Accessed 2026-05-11}
}