Menezesite

Ba3MgZr4Nb12O42 · 12H2O
IMA status
  • Approved
IMA symbol
Mze
IMA approved
2005
Also known as
  • IMA2005-023
  • Menezesiet

Where it forms, where it's found

Geological setting

Contact zone between dolomite carbonatite and “jacupirangite” (=a pyroxenite)

Type locality
Jacupiranga mine
  1. Cajati
  2. São Paulo
  3. Brazil

-24.6983°, -48.1259°

1recorded occurrences
Source · OpenStreetMap

Physical

Hardness
123456789104/ 10 MOHS
  1. 1Talc
  2. 2Gypsum
  3. 3Calcite
  4. 4Fluorite
  5. 5Apatite
  6. 6Orthoclase
  7. 7Quartz
  8. 8Topaz
  9. 9Corundum
  10. 10Diamond
Transparency
Transparent
Colour
Reddish brown
Streak
White
Cleavage

Cleavage not observed

Density
4.181 g/cm³

Optical

Optical type
Isotropic
UV response
None
Notes

n>1.93(meas), calculated = 2.034

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

Crystallography

Crystal system
Isometric
Space group
#203
Cell parameters
a = 13.017(1) Å
Z
2
Type-locality form

Rhombododecahedra up to 1 mm, isolated or in aggregates.

Crystal structure

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
41NbNiobiumNiobium1292.9061114.872
39.76%
8OOxygenOxygen5415.999863.946
30.81%
56BaBariumBarium3137.327411.981
14.69%
40ZrZirconiumZirconium491.224364.896
13.01%
12MgMagnesiumMagnesium124.30524.305
0.87%
1HHydrogenHydrogen241.00824.192
0.86%
Total2804.192100.00%

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

From IMA formula

Synonyms

  • IMA2005-023
  • Menezesiet

In other languages

German
IMA 2005-023 · Menezesit
Portuguese
IMA2005-023 · Menezesita

Classification

Strunz
10th ed.

4.FN.05

  • 4OxidesClass
  • 4.FHydroxides (without V or U)Division
  • 4.FNHydroxides with H2O±(OH); frameworks of corner and/or face-sharing octahedraGroup
  • 4.FN.05MenezesiteSpecies

Group, growth & confusion

Commonly confused with
1 mineral

Literature, links & citation

Citations
  1. 2006Atencio, D., Couthino, J.M.V., Doriguetto, A.C., Mascarenhas, Y.P., Ellena, J.A., Ferrari, V.C. (2006) Menezesite from Cajati, São Paulo, Brazil: The first heteropolyniobate mineral. 19th General Meeting of the International Mineralogical Association, IMA2006, 299pp.
  2. 2008Atencio, D., Coutinho, J. M.V., Doriguetto, A. C., Mascarenhas, Y. P., Ellena, J., Ferrari, V. C. (2008) Menezesite, the first natural heteropolyniobate, from Cajati, Sao Paulo, Brazil: Description and crystal structure. American Mineralogist, 93 (1) 81-87 doi:10.2138/am.2008.2536 DOI: 10.2138/am.2008.2536
  3. 2021(2021) Menezesite. Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Menezesite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/menezesite-27607},
  note      = {Accessed 2026-05-11}
}