Amblygonite, Lepidolite, Petalite, Quartz, Spodumene
Abija N. Fillow Quarry (Branchville Quarry), Branchville, Redding, Fairfield Co., Connecticut, USA
is a rare silicate mineral and is one of very few silicate
minerals that have a trigonal symmetry. It is a member
of the Phenakite Group of minerals that includes Eucryptite,
All three have the same basic chemical structure and
symmetry, but different metal ions. Eucryptite can fluoresce
a beautiful magenta red to orangish-red under shortwave (SW)
light (put your mouse over the picture above to see the
gems color under SW-UV light).
was named in 1880 by American mineralogists George J.
Brush (1831-1912) and Edward S. Dana (1849-1935) from the Greek words
for well and concealed, in reference to
its occurrence as intimate intergrowths with Albite.
can be found in the USA, from Branchville, Fairfield
County, Connecticut; Center Strafford, Strafford County,
New Hampshire; in the Harding pegmatite, Dixon, Taos
County, New Mexico; in the Midnight Owl pegmatite, Maricopa
County, Arizona; and in the Foote mine, Kings Mountain,
Cleveland County, North Carolina. From the Tanco pegmatite,
Bernic Lake, Manitoba, and near Nakina, Ontario, Canada.
In Zimbabwe, large amounts at Bikita, with many other
minor localities. From the Haapaluoma quarry, near Peräseinäjoki,