Mineralpedia Details for Microlite
Microlite
Refers to a group of minerals, named for the Greek word micros, meaning “small,” as the crystals from the type locality at Clark Ledge in Massachusetts, USA are typically quite small. Microlite has a few hundred localities but only a few are known for large crystals. It occurs in lithium rich granite pegmatites including here in the Black Hills of South Dakota in the Tin Mountain, Shamrock No. 1, White Cap (King Lithia), Peerless, and Bob Ingersoll mines in the United States. Microlite can also be found replacing tantalum minerals in these pegmatites and in crystal lined granite cavities. On occasion, Microlite can be radioactive.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/microlite.pdf
- Formula
- (Na,Ca)2Ta2O6(O,OH,F)
- Crystal System
- Isometric
- Crystal Habit
- Disseminated, Pseudo Octohedral
- Cleavage
- Indistinct, Indistinct, Indistinct
- Luster
- Vitreous - Resinous
- Color
- yellowish brown, reddish brown, greenish brown, green, gray
- Streak
- light yellow
- Class
- Isometric - Hexoctahedral
- Fracture
- Sub Conchoidal
- Hardness
- 5-5.5
- WebMineral
- View Microlite
- Mindat
- View Microlite
Microlite from Ipe mine, Governador Valaderas, Minas Gerais, Brazil
Glassy orange fine octahedral crystals from 0.5 to 1mm associated with green crystals of Muscovite on Albite matrix.
Gemmy, octahedral micro crystals to 0.75mm on cleavelandite matrix.
Glassy orange, octahedral crystals from 1-2mm, twinned.
Microlite from Harding mine, Taos Co., New Mexico, United States
Yellow crystal grains to 1.5mm throughout purple Lepidolite matrix.
Microlite from Hollister quarry, near South Glastonbury, Hartford Co., Connecticut, United States
Brown 6mm rounded crystal.
Microlite from Rutherford mines, Amelia Co., Virginia, United States
Well-formed, very nice 4mm complex crystal.
