Homilite
A brown gadolinite-group calcium-iron borosilicate found in Norwegian pegmatites since 1876.
Intro adapted from Wikipedia (CC BY-SA).
Homilite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca₂Fe²⁺B₂Si₂O₁₀.
It crystallizes in the monoclinic crystal system (space group P2_1/a). It is a member of the Gadolinite structural group.
Key properties: Mohs hardness 5; specific gravity 3.34–3.38; Grayish streak; Resinous to vitreous luster; optically biaxial.
IMA symbol Hom, grandfathered status — known before the IMA’s founding, named in 1876.
Found in pegmatite.
It is found associated with Allanite, meliphanite, titanite, zircon, aegirine, lÄollingite, astrophyllite, melanocerite, nordenskiÄoldine, wÄohlerite, hiortdahlite, molybdenite.
Its name comes from the Greek for to occur together, in allusion to its association with meliphanite and \erdmannite" (allanite).