GRapi = 3,545,303.50 (Gamma Ray American Petroleum Institute Units)
Contains uranium - always wash hands after handling. Avoid inhaling dust when
handling or breaking. Never lick or ingest. Avoid prolonged exposure in
proximity of the body. Store away from inhabited areas.
is a rare barium lead uranyl vanadate mineral that is
strongly radioactive due
to its uranium content. Francevillite occurs in the oxidized
zone of lead-bearing uranium–vanadium deposits. It was first described in 1957 from an occurrence at
the Mounana (uranium) Mine, near Franceville, Haut-Ogooué, Gabon and was named for the nearby
city of Franceville. Francevillite occurs as crystals to
about 8 mm, and as aggregates, massive, in veinlets
and as impregnations. Its colors range from lemon-yellow
to yellow-orange and orange, greenish yellow, green
and brown. Francevillite is semi-transparent with
adamantine to pearly luster, strong dispersion and Mohs
hardness of 3.
distribution: exceptional crystals from the Mounana
uranium Mine, Franceville, Gabon. At Kambove and in
the Musonoi mine, near Kolwezi, Katanga Province, Congo
(Shaba Province, Zaire). On the southwest edge of the
Chimeja Range, about four km north of Lubimbi Spring,
Zimbabwe. From Bertholène and Lussagues, Aveyron,
and Saint-Pierre, Cantal, France. In Germany, on the
Donnersberg, near Imsbach, Rhineland-Palatinate; in
the Black Forest, at Nussbach, near Triberg, and from
the Clara mine, near Oberwolfach. In the South Terras
mine, St. Stephen-in-Brannel, Cornwall, England. At
the Tyuya-Muyun Cave, Fergana Valley, Alai Range, Kyrgyzstan.
From the Otish Mountains, Quebec, Canada. In the USA,
at Jim Thorpe, Carbon County, Pennsylvania.
gems for sale:
have not photographed our Francevillite
gems yet. Please
check back soon.