No images
Formula: Na2NaBaCeZnSi6O17
Inosilicate (chain silicate), nordite group
Crystal System: Orthorhombic
Specific gravity: 3.65 calculated
Colour: Pinkish
Environments
Pegmatites
Hydrothermal environments
Illoqite-(Ce) is a new mineral, approved in 2021, and to date (March 2022) reported only from the type
locality.
Localities
At the type locality, the Taseq Slope, Ilímaussaq complex, Kujalleq, Greenland, illoqite-(Ce) occurs in a
hyperalkaline ussingite vein closely related to one of the largest
ussingite veins in the Ilímaussaq complex. The associated minerals are
aegirine, arfvedsonite,
a britholite-group mineral,
epistolite, chkalovite,
lueshite, a
manganese-rich pectolite
group member and steenstrupine-(Ce). Illoqite-(Ce)
crystallises as either single euhedral crystals up to 150 μm in size or radiating aggregates consisting of a
few or many crystals. The aggregates are up to 200 μm in diameter. Illoqite-(Ce) can occur as scattered small
groups of crystals or aggregates, but sometimes they occur in high concentrations creating clusters or bands
almost completely consisting of illoqite-(Ce).
Alongside ussingite as a matrix mineral,
aegirine and arfvedsonite
occur as major components. Furthermore, the paragenesis of illoqite-(Ce) consists of
britholite-(Ce),
ancylite-(Ce),
epistolite, chkalovite,
lueshite,
steenstrupine-(Ce) and
polylithionite, where
ancylite-(Ce) is the brownish weathering product of
illoqite-(Ce)
(MM 86.1.141-149).
Back to Minerals