Madeiraite

Where it forms, where it's found

Type locality: Terra do Baptista gabbro outcrop
Porto da Cruz
Machico
Madeira Island
Madeira
Portugal
32.7671°, -16.8416°

2recorded occurrences

Source · OpenStreetMap

Crystallography

Crystal system: Monoclinic
Space group: P21/a
Cell parameters: a = 10.880(1) Å · b = 10.0442(7) Å · c = 7.2250(7) Å
Cell angles: β = 108.78(1) °
Ratio a:b:c: 1 : 0.923 : 0.664

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
8OOxygen Oxygen 16 15.999 255.984
30.97%
40ZrZirconium Zirconium 2 91.224 182.448
22.07%
14SiSilicon Silicon 4 28.085 112.340
13.59%
26FeIron Iron 2 55.845 111.690
13.51%
20CaCalcium Calcium 2 40.078 80.156
9.70%
11NaSodium Sodium 2 22.990 45.980
5.56%
9FFluorine Fluorine 2 18.998 37.996
4.60%
Total 826.594 100.00%
Mass share = atoms × atomic mass ÷ molar mass × 100
From IMA formula

Mass composition breakdown
Element	Atoms	At. mass g/mol	Mass g/mol	Mass share
8OOxygen	Oxygen	16	15.999	255.984	30.97%
40ZrZirconium	Zirconium	2	91.224	182.448	22.07%
14SiSilicon	Silicon	4	28.085	112.340	13.59%
26FeIron	Iron	2	55.845	111.690	13.51%
20CaCalcium	Calcium	2	40.078	80.156	9.70%
11NaSodium	Sodium	2	22.990	45.980	5.56%
9FFluorine	Fluorine	2	18.998	37.996	4.60%
	Total	826.594	100.00%

Synonyms

Madeiraiet

In other languages

German: IMA 2021-077 · Madeirait
Portuguese: madeiraíte

Classification

Strunz

10th ed.

9.BE

9SilicatesClass
9.BSorosilicatesDivision
9.BESi₂O₇ groups, with additional anions; cations in octahedral [6] and greater coordinationGroup
9.BEMadeiraiteSpecies

Group, growth & confusion

11 members

1 mineral

PilanesbergiteNa₂Ca₂Fe₂Ti₂(Si₂O₇)₂O₂F₂
Mineral
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Literature, links & citation

Citations

2022(2022) Madeiraite. Handbook of Mineralogy. Mineralogical Society of America

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Madeiraite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/madeiraite-55695},
  note      = {Accessed 2026-05-11}
}