Giacovazzoite

K5Fe3+3O(SO4)6 · 10H2O
IMA status
  • Approved
IMA symbol
Gvz
IMA approved
2019
Also known as
  • Giacovazzoiet
  • IMA2018-165

Where it forms, where it's found

Type locality
Monte Arsiccio Mine
  1. Sant'Anna di Stazzema
  2. Stazzema
  3. Lucca Province
  4. Tuscany
  5. Italy

43.9654°, 10.2836°

1recorded occurrences
Source · OpenStreetMap

Physical

Colour
Orange–brown
Streak
yellowish
Tenacity
brittle
Cleavage
Perfect

(100)

Crystallography

Crystal system
Monoclinic
Space group
P21/c
Cell parameters
a = 9.4797(2) Å · b = 18.4454(5) Å · c = 18.0540(4) Å
Cell angles
β = 92.626(2) °
Ratio a:b:c
1 : 1.946 : 1.904
Z
4
Type-locality form

Orange–brown prismatic crystals, up to 0.1 mm long.

Crystal structure

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
8OOxygenOxygen3515.999559.965
49.31%
19KPotassiumPotassium539.098195.490
17.22%
16SSulfurSulfur632.060192.360
16.94%
26FeIronIron355.845167.535
14.75%
1HHydrogenHydrogen201.00820.160
1.78%
Total1135.510100.00%

Mass share = atoms × atomic mass ÷ molar mass × 100

From IMA formula

Synonyms

  • Giacovazzoiet
  • IMA2018-165

In other languages

German
Giacovazzoit · IMA 2018-165

Classification

Strunz
10th ed.

7.DF.55

  • 7SulfatesClass
  • 7.DSulfates (selenates, etc.) with additional anions, with H2ODivision
  • 7.DFWith large and medium-sized cationsGroup
  • 7.DF.55GiacovazzoiteSpecies

Literature, links & citation

Citations
  1. 2019Biagioni, C., Mauro, D., Bindi, L., Hålenius, U., & Pasero, M. (2019). Giacovazzoite and scordariite, two new minerals related to metavoltine. In Il tempo del Pianeta Terra e il tempo dell'uomo: Le geoscienze fra passato e futuro. ITA.
  2. 2019Miyawaki, Ritsuro, Hatert, Frédéric, Mills, Stuart J. (2019) New minerals and nomenclature modifications approved in 2019. CNMNC Newsletter 49. Mineralogical Magazine, 83 (3) 479-483 doi:10.1180/mgm.2019.35 DOI: 10.1180/mgm.2019.35
  3. 2020Biagioni, Cristian; Bindi, Luca; Mauro, Daniela; Pasero, Marco (2020) Crystal-chemistry of sulfates from the Apuan Alps (Tuscany, Italy). IV. Giacovazzoite, K5Fe3+3O(SO4)6(H2O)9·H2O, the natural analogue of the β-Maus’s Salt and its dehydration product. Physics and Chemistry of Minerals, 47 (1). 7 doi:10.1007/s00269-019-01076-4DOI: 10.1007/s00269-019-01076-4
  4. 2022(2022) Giacovazzoite. Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Giacovazzoite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/giacovazzoite-53567},
  note      = {Accessed 2026-05-11}
}