Withamite

Where it forms, where it's found

2recorded occurrences

Source · OpenStreetMap

Physical

Colour: pink · red

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
8OOxygen Oxygen 13 15.999 207.987
38.65%
14SiSilicon Silicon 3 28.085 84.255
15.65%
20CaCalcium Calcium 2 40.078 80.156
14.89%
26FeIron Iron 1 55.845 55.845
10.38%
25MnManganese Manganese 1 54.938 54.938
10.21%
13AlAluminium Aluminium 2 26.982 53.964
10.03%
1HHydrogen Hydrogen 1 1.008 1.008
0.19%
Total 538.153 100.00%
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
8OOxygen	Oxygen	13	15.999	207.987	38.65%
14SiSilicon	Silicon	3	28.085	84.255	15.65%
20CaCalcium	Calcium	2	40.078	80.156	14.89%
26FeIron	Iron	1	55.845	55.845	10.38%
25MnManganese	Manganese	1	54.938	54.938	10.21%
13AlAluminium	Aluminium	2	26.982	53.964	10.03%
1HHydrogen	Hydrogen	1	1.008	1.008	0.19%
	Total	538.153	100.00%

Synonyms

Withamit

Literature, links & citation

Citations

—W. E. Tröger: "Tabellen zur optischen Bestimmung der gesteinsbildenden Minerale", Schweizerbart (Stuttgart), 1952
1897C. Hintze: "Handbuch der Mineralogie", Vol. 2 (1897)

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Withamite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/withamite-26933},
  note      = {Accessed 2026-05-11}
}