Hydrokenopyrochlore

(◻,Sb3+,Na)2Nb2O6 · H2O
IMA status
  • Approved
IMA symbol
Hkpcl
IMA approved
2017
Also known as
  • Hydrokenopyrochloor
  • IMA2017-005

Where it forms, where it's found

Geological setting

A complex type LCT pegmatite hosted in a metadolomite.

Type locality
Antandrokomby pegmatite
  1. Manandona Valley
  2. Sahatsiho Ambohimanjaka
  3. Ambositra District
  4. Amoron'i Mania
  5. Madagascar

-20.2402°, 47.0220°

2recorded occurrences
Source · OpenStreetMap

Physical

Colour
Tan to beige
Streak
white
Fracture
Irregular/Uneven
Density
5.08 g/cm³

Optical

Notes

The mean refractive index, obtained from the Gladstone–Dale relationship and the calculated density, is 2.074 (on the basis of the empirical formula).

Isotropy testPPL ↔ XPL diagnostic
PPL intrinsic colour; no change on stage rotation
XPL extinct at every orientation

Crystallography

Crystal system
Isometric
Space group
Fd-3m
Cell parameters
a = 10.4887(8) Å
Unit cell volume
1153.9 ų
Z
8
Type-locality form

Tan to beige subhedral crystals, up to 1mm in size.

Synonyms

  • Hydrokenopyrochloor
  • IMA2017-005

In other languages

German
Hydrokenopyrochlor · IMA 2017-005

Classification

Strunz
10th ed.

4.DH.15

  • 4OxidesClass
  • 4.DMetal: Oxygen = 1:2 and similarDivision
  • 4.DHWith large (+- medium-sized) cations; sheets of edge-sharing octahedraGroup
  • 4.DH.15HydrokenopyrochloreSpecies

Group, growth & confusion

Literature, links & citation

Citations
  1. 2017Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2017) New minerals and nomenclature modifications approved in 2017, CNMNC Newsletter No 37. Mineralogical Magazine, 81 (3) 737-742 doi:10.1180/minmag.2017.081.039DOI: 10.1180/minmag.2017.081.039
  2. 2018Biagioni, Cristian, Meisser, Nicolas, Nestola, Fabrizio, Pasero, Marco, Robyr, Martin, Roth, Philippe, Schnyder, Cédric, Gieré, Reto (2018) Hydrokenopyrochlore, (□,#)2Nb2O6·H2O, a new species of the pyrochlore supergroup from the Sahatany Pegmatite Field, Antananarivo Province, Madagascar. European Journal of Mineralogy, 30 (4) 869-876 doi:10.1127/ejm/2018/0030-2761DOI: 10.1127/ejm/2018/0030-2761
  3. 2020Pezzotta, Federico, Preite, Domenico (2020) Idrokenopirocloro di Antandrokomby, Madagascar: una breve storia. Micro, 18 (1). 46-49
  4. 2022(2022) Hydrokenopyrochlore. Handbook of Mineralogy. Mineralogical Society of America
  5. 2023Larsen, Knut Edvard (2023) Minerals first described from Madagascar. Norsk Mineralsymposium 2023, 89-122
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Hydrokenopyrochlore — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/hydrokenopyrochlore-51831},
  note      = {Accessed 2026-05-11}
}