Maghagendorfite

Where it forms, where it's found

Geological setting: complex zoned granite pegmatite.
Type locality: Dike Lode
Keystone Mining District
Pennington County
South Dakota
USA
43.8567°, -103.4047°

5recorded occurrences

Source · OpenStreetMap

Physical

Hardness: 1Talc
2Gypsum
3Calcite
4Fluorite
5Apatite
6Orthoclase
7Quartz
8Topaz
9Corundum
10Diamond
Transparency: Translucent
Colour: greenish black
Cleavage: Distinct/Good
Good on (001); poor on (110) (by analogy to hagendorfite)

Optical

Optical type: Biaxial

Crystallography

Crystal system: Monoclinic
Comment: Space Group: n.d. Z = n.d.

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
8OOxygen Oxygen 12 15.999 191.988
41.12%
26FeIron Iron 2 55.845 111.690
23.92%
15PPhosphorus Phosphorus 3 30.974 92.922
19.90%
11NaSodium Sodium 2 22.990 45.980
9.85%
12MgMagnesium Magnesium 1 24.305 24.305
5.21%
Total 466.885 100.00%
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	12	15.999	191.988	41.12%
26FeIron	Iron	2	55.845	111.690	23.92%
15PPhosphorus	Phosphorus	3	30.974	92.922	19.90%
11NaSodium	Sodium	2	22.990	45.980	9.85%
12MgMagnesium	Magnesium	1	24.305	24.305	5.21%
	Total	466.885	100.00%

Synonyms

Maghagendorfiet
Maghagendorfite-Na[]

In other languages

German: Maghagendorfit
Spanish: Maghagendorfita
Italian: maghagendorfite

Classification

Strunz

10th ed.

8.AC.10

8Phosphates, Arsenates, VanadatesClass
8.APhosphates, etc. without additional anions, without H₂ODivision
8.ACWith medium-sized and large cationsGroup
8.AC.10MaghagendorfiteSpecies

Dana

8th ed.

38.02.03.04

38Anhydrous Normal Phosphates, Arsenates, and VanadatesClass
38.02(AB)₅(XO₄)₃Type
38.02.03Alluaudite-Wyllieite Group (Alluaudite Subgroup)Group
38.02.03.04MaghagendorfiteSpecies

CIM

—

19.12.49

19PhosphatesClass
19.12Phosphates of MnGroup
19.12.49MaghagendorfiteSpecies

Group, growth & confusion

26 members

Literature, links & citation

Citations

1979Moore, Paul B., Ito, Jun (1979) Alluaudites, wyllieites, arrojadites: crystal chemistry and nomenclature. Mineralogical Magazine, 43 (326) 227-235 doi:10.1180/minmag.1979.043.326.04 DOI: 10.1180/minmag.1979.043.326.04
1980Fleischer, Michael, Cabri, Louis J., Chao, G. Y., Pabst, Adolf (1980) New Mineral Names. American Mineralogist, 65 (7-8) 808-814
1992Robinson, George W., Van Velthuizen, Jerry, Ansell, H. Gary, Sturman, B. Darko (1992) Mineralogy of the Rapid Creek and Big Fish River Area, Yukon Territory. The Mineralogical Record, 23 (4) 1-47
2005(2005) Maghagendorfite. Handbook of Mineralogy. Mineralogical Society of America
2009Łodziński, M., Sitarz, M. (2009) Chemical and spectroscopic characterization of some phosphate accessory minerals from pegmatites of the Sowie Góry Mts, SW Poland. Journal of Molecular Structure, 924-926. 442-447 doi:10.1016/j.molstruc.2008.11.019DOI: 10.1016/j.molstruc.2008.11.019

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Maghagendorfite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/maghagendorfite-2532},
  note      = {Accessed 2026-05-11}
}