Where it forms, where it's found
- Geological setting
Zoned granitic phosphate pegmatite.
- Type locality
- Hagendorf South Pegmatite
- Hagendorf
- Waidhaus
- Neustadt an der Waldnaab District
- Upper Palatinate
- Bavaria
- Germany
49.6503°, 12.4597°
2recorded occurrences
Physical
Optical
- Optical type
- Biaxial (-) · 2V measured = 87°
- Refractive index
- 1.763 – 1.797
- Surface relief
- High
- Principal indices
- nα 1.763 · nβ 1.781 · nγ 1.797
- Pleochroism
- Visible
X = blue green, Y = olive green, Z = yellow brown.
- Dispersion
- Strong
- Notes
β is calculated. X = c, Y = a, Z = b. Absorption X ≈ Y > Z.
Δ = 0Δmax
PPLpleochroism per grain
XPLindependent extinctions · rotate the stage
PPLpleochroism only · colour blends on rotation
XPLinterference colour · extinct every 90°
Retardation340 nm
Order1st order
XPL colour
Crystallography
- Cell parameters
- a = 13.994(1) Å · b = 16.884(1) Å · c = 5.1866(4) Å
- Ratio a:b:c
- 1 : 1.207 : 0.371
- Z
- 4
- Morphology
Blades are flattened on (010) and elongated on [001].
- Type-locality form
Densely packed, lustrous, black blades. Individual blades are up to 2 mm in length and roughly 10 µm thick.
- Comment
Space group is Bbmm
Crystal structure
Chemical composition
Synonyms
- Ferrorockbridgeiet
- IMA2018-004
In other languages
- German
- Ferrorockbridgeit · IMA 2018-004
Classification
Strunz
10th ed.8.BC.10
- 8Phosphates, Arsenates, VanadatesClass
- 8.BPhosphates, etc., with additional anions, without H2ODivision
- 8.BCWith only medium-sized cations, (OH, etc.):RO4 > 1:1 and < 2:1Group
- 8.BC.10FerrorockbridgeiteSpecies
Group, growth & confusion
Literature, links & citation
Citations
- 2018Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2018) CNMNC Newsletter No 43, New minerals and nomenclature modifications approved in 2018. Mineralogical Magazine, 82 (3) 779-785 doi:10.1180/mgm.2018.72DOI: 10.1180/mgm.2018.72
- 2019Grey, Ian E., Kampf, Anthony R., Keck, Erich, Cashion, John D., MacRae, Colin M., Gozukara, Yesim, Peterson, Vanessa K., Shanks, Finlay L. (2019) The rockbridgeite group approved and a new member, ferrorockbridgeite, (Fe2+,Mn2+)2(Fe3+)3(PO4)3(OH)4(H2O), described from the Hagendorf Süd pegmatite, Oberpfalz, Bavaria. European Journal of Mineralogy, 31 (2) 389-397 doi:10.1127/ejm/2019/0031-2823DOI: 10.1127/ejm/2019/0031-2823
Cite this entry
@misc{mineral2026,
author = {Mineral Index editorial board},
title = {Ferrorockbridgeite — Mineral Index},
year = {2026},
url = {https://mineralindex.org/minerals/ferrorockbridgeite-52914},
note = {Accessed 2026-05-11}
}