Agrellite

agrellite

aegirine

eudialyte

miserite

Images

Formula: NaCa2Si4O10F
Inosilicate (chain silicate)
Crystal System: Triclinic
Specific gravity: 2.902 measured, 2.887 calculated
Hardness: 5½
Streak: White
Colour: White to greyish or greenish white
Luminexcence: Fluoresces bright pink under long wave UV and duller pink under short wave UV
Environments

Plutonic igneous environments
Pegmatites

Common associates of agrellite include aegirine, eudialyte, miserite and quartz (Mindat).

Localities

At the type locality, the Kipawa alkaline complex, Les Lacs-du-Témiscamingue, Témiscamingue RCM, Abitibi-Témiscamingue, Quebec, Canada, agrellite occurs in the regionally metamorphosed agpaitic rock complex. It is found in pegmatitic lenses and pods and in mafic gneisses composed principally of albite, microcline, alkalic amphibole (katophorite-arfvedsonite), aegirine-augite with or without eudialyte and nepheline; in addition, the following minerals are found in small but widely varying amounts: hiortdahlite, other members of the wöhlerite group, mosandrite-(Ce), miserite, britholite, vlasovite, calcite, fluorite, gittinsite, clinohumite, norbergite, zircon, biotite, phlogopite and galena. The commonest occurrence is in the pegmatitic pods which have probably resulted from partial melting of the agpaitic rocks during amphibolite facies metamorphism. Agrellite forms white to greyish or greenish white crystals from a few mm up to 100 mm in length (Canadian Mineralogist: 14: 120-126, HOM).
Agreiite from Kipawa - Image

At the Stettin pluton, Wausau Intrusive Complex, Marathon county, Wisconsin, USA, agrellite is associated with miserite, aegirine, eudialyte and quartz (HOM).

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