Locality: Kingman Feldspar Mine (Kingman group of claims; Kingman Feldspar Quarry; Kingman Feldspar Quarries), Kingman area, Wallapai District, Cerbat Mts (Cerbat Range), Mohave Co., Arizona, USA Dimensions: 2.7 cm x 2.2 cm x 1.5 cm Allanite(Nd) with Allanite(Ce). — Photo: Raúl Jorge Tauber Larry · CC0
Allanite-(Nd)
Allanite-(Nd) is an IMA-recognized mineral species in the silicate class, with the chemical formula CaNd(Al₂Fe²⁺)[Si₂O₇][SiO₄]O(OH).
It crystallizes in the monoclinic crystal system (space group P2_1/m). It is a member of the Epidote, allanite structural group.
Key properties: Mohs hardness 6; specific gravity 3.98; Grayish brown streak; Vitreous luster; optically biaxial.
IMA symbol Aln-Nd, IMA status: approved, named in 2010.
An accessory phase in the blocky zone of a NYF-type granitic pegmatite (Sweden).
It is found associated with Iimoriite-(Y), keiviite-(Y), allanite-(Y), tengerite-(Y).
The suffix identifies the Nd-analog of allanite-(Ce). Honors Thomas Allan (1777-1833), Scottish mineralogist who discovered the species.