Iceland Spar

Where it forms, where it's found

48recorded occurrences

Source · OpenStreetMap

Physical

Colour: Clear

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
8OOxygen Oxygen 3 15.999 47.997
47.96%
20CaCalcium Calcium 1 40.078 40.078
40.04%
6CCarbon Carbon 1 12.011 12.011
12.00%
Total 100.086 100.00%
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	3	15.999	47.997	47.96%
20CaCalcium	Calcium	1	40.078	40.078	40.04%
6CCarbon	Carbon	1	12.011	12.011	12.00%
	Total	100.086	100.00%

Synonyms

Cristallus islandica
Crystallus talcosa seu Islandica
Doppelspat
Doppelstein
Icelandic Spar
Islandspat
Spatum pellucidum objecta duplicans

Literature, links & citation

Citations

1888Hastings (1888) American Journal of Science: 35: 60.
1890Offret (1890) Bulletin de la Société française de Minéralogie: 13: 580.
1893Dufet (1893) Bulletin de la Société française de Minéralogie: 16: 157.
1902Gifford (1902) Proceedings of the Royal Society of London: 70: 336.
1916Hintze, Carl (1916) Handbuch der Mineralogie. Berlin and Leipzig. 6 volumes: vol. 1(3A): 2839.

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Iceland Spar — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/iceland-spar-4900},
  note      = {Accessed 2026-05-11}
}