RARE EARTH EPIDOTE FROM PEGMATITES OF THE MIDDLE URALS

Journal Article · Sat Aug 01 04:00:00 EDT 1959 · Doklady Akad. Nauk S.S.S.R.

OSTI ID:4221027

Mineev, D A

A rare-earth yttrium-bearing epidote was discovered in granite pegmatites in Slyuda mountain in the Middle Urals. The mineral appears in pegmatite vein No. 4 as black, lenticular, columnar, or isometric structure of several millimeters of 70 cm at its largest parameter. All rare-earth epidotes of the region have crystalline shapes with poorly outlined faces. They appear as elongated, plane-prismatic crystals of monocline syngony. The crystals are zonal with luster areas followed by dull areas; the mineral is friable, the microhardness is 943.8 kg/mm/sup 2/, the specific gravity is 3.29. The rare- earth epidote is radioactive but does not luminesce, is not electroconducting or magnetic. Radiochemical analysis showed 23 times rmore uranium than thorium (0.14% U and 0.006% Th). The content of the epidote in percent of total rare earths is: Ce, 7.8; Dy, 13.7; Er, 30.7; Eu, 1.0; Gd, 5.8; Ho, 3.9; La, 2.4; Lu, 3.9; Nd, 2.4; Pr, 1.0; Sm, 2.0; Tb, 1.0; Tu, 4.9; and Yb, 19.5. In addition, Cu, Ga, Mg, Na, and Ni and traces of Le, Pb, Se, and Sn were found. The age of the mineral is --1.0 x 10/sup 9/ years. (R.V.J.)

• Research Organization: Inst. of Mineralogy, Geochemistry and Crystal Chemistry of Rare Elements, Academy of Sciences, U.S.S.R.
• NSA Number: NSA-13-021046
• OSTI ID: 4221027
• Journal Information: Doklady Akad. Nauk S.S.S.R., Journal Name: Doklady Akad. Nauk S.S.S.R. Vol. Vol: 127
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

AGE ESTIMATION
ALUMINUM SILICATES
CALCIUM SILICATES
CRYSTALS
EPIDOTE
GEOLOGY AND MINERALOGY
GRANITES
IGNEOUS ROCKS
OPTICAL SYSTEMS
PEGMATITES
RADIOACTIVITY
RADIOCHEMISTRY
RARE EARTHS
ROCKS
THORIUM
TRACE AMOUNTS
URANIUM
YTTRIUM COMPOUNDS