Ferriakasakaite-(La)

CaLaFe3+AlMn2+(Si2O7)(SiO4)O(OH)
IMA status
  • Approved
IMA symbol
Fak-La
IMA approved
2013
Also known as
  • Ferriakasakaiet-(La)
  • IMA2013-126

Where it forms, where it's found

Geological setting

In tephroite ± calcite veinlets cutting a stratiform ferromanganese deposit.

Type locality
Shobu manganese deposit
  1. Shobu
  2. Ise City
  3. Mie Prefecture
  4. Japan
3recorded occurrences
Source · OpenStreetMap

Crystallography

Crystal system
Monoclinic
Space group
P21/m
Cell parameters
a = 8.8733(2) Å · b = 5.7415(1) Å · c = 10.0805(3) Å
Cell angles
β = 113.845(2) °
Ratio a:b:c
1 : 0.647 : 1.136
Unit cell volume
469.73 ų
Crystal structure

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
8OOxygenOxygen1315.999207.987
34.10%
57LaLanthanumLanthanum1138.905138.905
22.77%
14SiSiliconSilicon328.08584.255
13.81%
26FeIronIron155.84555.845
9.15%
25MnManganeseManganese154.93854.938
9.01%
20CaCalciumCalcium140.07840.078
6.57%
13AlAluminiumAluminium126.98226.982
4.42%
1HHydrogenHydrogen11.0081.008
0.17%
Total609.998100.00%

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

From IMA formula

Synonyms

  • Ferriakasakaiet-(La)
  • IMA2013-126

In other languages

German
Ferriakasakait-(La) · IMA 2013-126
Italian
ferriakasakaite-(La)
Japanese
ランタンフェリ赤坂石

Classification

Strunz
10th ed.

9.BG.05b

  • 9SilicatesClass
  • 9.BSorosilicatesDivision
  • 9.BGSorosilicates with mixed SiO4 and Si2O7 groups; cations in octahedral [6] and greater coordinationGroup
  • 9.BG.05bFerriakasakaite-(La)Species

Group, growth & confusion

In the same group
23 members
Commonly confused with
1 mineral

Literature, links & citation

Citations
  1. 2006Armbruster, Thomas, Bonazzi, Paola, Akasaka, Masahide, Bermanec, Vladimir, Chopin, Christian, Gieré, Reto, Heuss-Assbichler, Soraya, Liebscher, Axel, Menchetti, Silvio, Pan, Yuanming, Pasero, Marco (2006) Recommended nomenclature of epidote-group minerals. European Journal of Mineralogy, 18 (5) 551-567 doi:10.1127/0935-1221/2006/0018-0551DOI: 10.1127/0935-1221/2006/0018-0551
  2. 2014Williams, P. A., Hatert, F., Pasero, M., Mills, S. J. (2014) New minerals and nomenclature modifications approved in 2014, CNMNC Newsletter No 20. Mineralogical Magazine, 78 (3) 549-558 doi:10.1180/minmag.2014.078.3.05DOI: 10.1180/minmag.2014.078.3.05
  3. 2015Nagashima, Mariko, Nishio-Hamane, Daisuke, Tomita, Norimitsu, Minakawa, Tetsuo, Inaba, Sachio (2015) Ferriakasakaite-(La) and ferriandrosite-(La): new epidote-supergroup minerals from Ise, Mie Prefecture, Japan. Mineralogical Magazine, 79 (3) 735-753 doi:10.1180/minmag.2015.079.3.16DOI: 10.1180/minmag.2015.079.3.16
  4. 2022(2022) Ferriakasakaite-(La). Handbook of Mineralogy. Mineralogical Society of America
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Ferriakasakaite-(La) — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/ferriakasakaite-la-45983},
  note      = {Accessed 2026-05-11}
}