Where it forms, where it's found
- Geological setting
High-temperature fumarole (~400°C), altered pyroclastic breccia.
- Type locality
- La Fossa crater
- Vulcano Island
- Lipari
- Eolie Islands (Aeolian Islands)
- Metropolitan City of Messina
- Sicily
- Italy
38.4034°, 14.9614°
2recorded occurrences
Safety & handling
Physical
- Density
- 5.932 g/cm³
Optical
- UV response
- Not fluorescent.
- Notes
The mean index of refraction is 2.0(1).
Crystallography
- Space group
- #14
- Cell parameters
- a = 8.9477(6) Å · b = 7.9218(7) Å · c = 12.4955(5) Å
- Cell angles
- β = 90.092(4) °
- Ratio a:b:c
- 1 : 0.885 : 1.397
- Morphology
Tabular on (010). Forms at the type location include: (010), (101), (110), (100), (001), and (011).
- Type-locality form
Aggregates of pale yellow-green tabular crystals up to 0.1 mm in length.
Crystal structure
Chemical composition
Synonyms
- Hephaistosiet
- IMA2006-043
In other languages
- German
- Hephaistosit · IMA 2006-043
- Italian
- hephaistosite
Classification
Strunz
10th ed.3.AA.60
- 3HalidesClass
- 3.ASimple halides, without H2ODivision
- 3.AAM:X = 1:1, 2:3, 3:5, etc.Group
- 3.AA.60HephaistositeSpecies
Group, growth & confusion
Literature, links & citation
Citations
- 2005Zelenski, Michael, Bortnikova, Svetlana (2005) Sublimate speciation at Mutnovsky volcano, Kamchatka. European Journal of Mineralogy, 17 (1) 107-118 doi:10.1127/0935-1221/2005/0017-107DOI: 10.1127/0935-1221/2005/0017-107
- 2008Campostrini, I., Demartin, F., Gramaccioli, C. M., Orlandi, P. (2008) Hephaistosite, TlPb2Cl5, a new thallium mineral series from La Fossa Crater, Vulcano, Aeolian Islands, Italy. The Canadian Mineralogist, 46 (3) 701-708 doi:10.3749/canmin.46.3.701 DOI: 10.3749/canmin.46.3.701
- 2009Mitolo, D., Pinto, D., Garavelli, A., Bindi, L., Vurro, F. (2009) The role of the minor substitutions in the crystal structure of natural challacolloite, KPb2Cl5, and hephaistosite, TlPb2Cl5, from Vulcano (Aeolian Archipelago, Italy) Mineralogy and Petrology, 96 (1) 121-128 doi:10.1007/s00710-008-0041-2DOI: 10.1007/s00710-008-0041-2
- 2011(2011) Hephaistosite. Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
author = {Mineral Index editorial board},
title = {Hephaistosite — Mineral Index},
year = {2026},
url = {https://mineralindex.org/minerals/hephaistosite-31407},
note = {Accessed 2026-05-11}
}