Mineralpedia Details for Uranocircite
Uranocircite
Named for the uranium in the composition and for the discovery locality at Falkenstein, which means Falcon’s Stone, after the Greek goddess Circe, which translates to “falcon.” Notable localities for Uranocircite include in the United States in Arizona, Utah, Pennsylvania, and here in the Black Hills of South Dakota at the Hart Table prospect, at Minas Gerais in Brazil, in Germany at the type locality at Bergen an der Trieb and at Schneeberg in Saxony, at Wolsendorf in Bavaria, and at Menzenschwand in the Schwarzwald Mountains, in the Czech Republic at Dametice in Bohemia, and in Spain at El Cabril in Cordoba. There are several other known localities. Uranocircite appears as yellow-green to yellow thin tabular crystals and as aggregates. It fluoresces green under ultraviolet light.
Ref. Minerals and their Localities, Bernard, J.H. and Hyršl, J. (2004)
IMA/CNMNC List of Mineral Names (2009) and Dana’s System of Mineralogy, 7th edition, 2 (1951), 987
- Formula
- Ba(UO2)2(PO4)2*12(H2O)
- Crystal System
- Tetragonal
- Crystal Habit
- Foliated, Tabular
- Cleavage
- Perfect, Distinct, None
- Luster
- Pearly
- Color
- yellow, yellow green
- Streak
- light yellow
- Class
- Tetragonal - Ditetragonal Dipyramidal
- Fracture
- Flexible
- Hardness
- 2-2.5
- WebMineral
- View Uranocircite
- Mindat
- View Uranocircite
Uranocircite from Bergen, Falkenstein, Vogtland, Saxony, Germany
1.3 cm yellowish green crystal.
Uranocircite from Mechelgrün, Plauen, Vogtland, Saxony, Germany
Bright yellowish green tabular, platy crystals to about 0.75mm.
Uranocircite from Johanngeorgenstadt, Erzgebirge, Saxony, Germany
Bright yellow tabular crystals to 2mm.
Uranocircite from Streuberg quarry, near Bergen, Vogtland, Germany
Yellow-green tabular crystals.
Uranocircite from São Pedro, Malacacheta dist., Minas Gerais, Brazil
This is the actual color. Bright neon greenish yellow thin tabular crystals to 4mm across. The specimen seems to glow in the daylight and is actually brighter than the photos. Originally from the late Carlos Barbosa.
