Images
Formulae:
gadolinite-(Ce):
Ce2Fe2+Be2O2(SiO4)2
gadolinite-(Nd):
Nd2Fe2+Be2O2(SiO4)2
gadolinite-(Y):
Y2Fe2+Be2O2(SiO4)2
Nesosilicates (insular SiO4 groups),
gadolinite subgroup,
gadolinite group,
gadolinite supergroup,
Localities
At Fairview, Stove Mountain, El Paso County, Colorado, USA, gadolinite-group minerals have been recovered from
the area, both in miarolitic cavities in pegmatites and in vugs
associated with quartz veins. Four different minerals in this group have been
identified here. Miarolitic cavities host black gadolinite-Ce crystals
that reach 1 mm and are associated with smoky quartz,
microcline, albite,
ilmenite, green fluorite,
fluocerite and bastnäsite.
Similar cavities produced gadolinite-(Y) crystals that are dark green
and occurred with crystals of smoky quartz,
microcline, zircon and
kainosite. Vugs in quartz veins
host chalky, light tan, 0.5 cm crystals of hingganite-(Y) and 0.5 mm
chalk-white to light tan masses of hingganite-(Yb). Both of these
minerals were associated with crystals of clear quartz,
magnetite, pyrite,
hematite and bertrandite
(R&M 97.5.418).
Back to Minerals