Milkovoite

Cu4O(PO4)(AsO4)
IMA status
  • Approved
  • Pending publication
IMA symbol
Milk
Also known as
  • IMA2021-005
  • Milkovoiet

Where it forms, where it's found

Type locality
Arsenatnaya fumarole
  1. Second scoria cone
  2. Northern Breakthrough (North Breach)
  3. Great Fissure eruption (Main Fracture)
  4. Tolbachik Volcanic field
  5. Milkovsky District
  6. Kamchatka Krai
  7. Russia

55.6833°, 160.2333°

1recorded occurrences
Source · OpenStreetMap

Safety & handling

Crystallography

Crystal system
Orthorhombic
Space group
Pnma
Cell parameters
a = 8.1865(7) Å · b = 6.3559(5) Å · c = 13.668(1) Å
Ratio a:b:c
1 : 0.776 : 1.670

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
29CuCopperCopper463.546254.184
50.43%
8OOxygenOxygen915.999143.991
28.57%
33AsArsenicArsenic174.92274.922
14.86%
15PPhosphorusPhosphorus130.97430.974
6.14%
Total504.071100.00%

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

From IMA formula

Synonyms

  • IMA2021-005
  • Milkovoiet

In other languages

German
IMA 2021-005 · Milkovoit

Classification

Strunz
10th ed.

8.BB

  • 8Phosphates, Arsenates, VanadatesClass
  • 8.BPhosphates, etc., with additional anions, without H2ODivision
  • 8.BBWith only medium-sized cations, (OH, etc.):RO4 about 1:1Group
  • 8.BBMilkovoiteSpecies

Literature, links & citation

Citations
  1. 2021Miyawaki, Ritsuro, Hatert, Frédéric, Pasero, Marco, Mills, Stuart J. (2021) IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 61. European Journal of Mineralogy, 33 (3) 299-304 doi:10.5194/ejm-33-299-2021 DOI: 10.5194/ejm-33-299-2021
  2. 2022(2022) Milkovoite. Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Milkovoite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/milkovoite-55452},
  note      = {Accessed 2026-05-11}
}