Blue John

Where it forms, where it's found

Type locality: Blue John Mine (Blue John Cavern)
Castleton
High Peak
Derbyshire
England
UK
53.3456°, -1.8035°

5recorded occurrences

Source · OpenStreetMap

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
20CaCalcium Calcium 1 40.078 40.078
51.33%
9FFluorine Fluorine 2 18.998 37.996
48.67%
Total 78.074 100.00%
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
20CaCalcium	Calcium	1	40.078	40.078	51.33%
9FFluorine	Fluorine	2	18.998	37.996	48.67%
	Total	78.074	100.00%

Literature, links & citation

Citations

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.

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Blue John — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/blue-john-698},
  note      = {Accessed 2026-05-11}
}