Mineralpedia Details for Uranophane
Uranophane
Sometimes referred to as Uranophane-alpha, Uranophane is named for its uranium content and for the Greek word phainesthai, meaning “to appear” as its composition was originally under some scrutiny as being accurate. Uranophane is quite common, a secondary mineral in uranium deposits and formed by the alteration of uraninite. It can also be found “as coatings, presumably through deposition from meteoric waters.” There are hundreds of worldwide localities, but only a few have excellent crystals or large quantities. Uranophane is highly radioactive. Crystals will fluoresce weakly under ultraviolet light, but massive Uranophane is typically not fluorescent.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/uranophane-alpha.pdf
- Formula
- Ca(UO2)2SiO3(OH)2*5(H2O)
- Crystal System
- Monoclinic
- Crystal Habit
- Radial, Earthy, Massive - Fibrous
- Cleavage
- Perfect, None, None
- Luster
- Vitreous (Glassy)
- Color
- yellow, yellow brown, yellow green, yellow orange, light yellow
- Streak
- yellowish white
- Class
- Monoclinic - Sphenoidal
- Fracture
- Uneven
- Hardness
- 2.5
- WebMineral
- View Uranophane
- Mindat
- View Uranophane
Uranophane from Valentine, Presidio Co., Texas, United States
2.5mm canary yellow radial spray of bladed crystals.
Uranophane from Madawaska Mine, Bancroft, Ontario, Canada
Light yellow, straw-like sprays of fibrous crystals to 1cm.
Uranophane from Freedom #1 Claim, Pinto Co., Utah, United States
Bright yellow acicular crystals to 0.75mm.
Uranophane from Faraday mine, Hastings Co., Ontario, Canada
Large, canary yellow fibrous crystal sprays to 1cm.
Uranophane from Zobes, Vogtland, Germany
Glassy, bright, yellow, prismatic crystals in radial sprays - to 2mm.
Uranophane from Margaritas mine, Sierra Peña Blanca, Chihuahua, Mexico
Bright yellow sprays of Uranophane to 1mm.
Uranophane from Grants dist., McKinley Co., New Mexico, United States
Bright yellow long acicular or fibrous crystals in groups to 2cm. Excellent specimen!
Uranophane from Musonoi mine, Kolwezi, Shaba Cu belt, DR of Congo
Superb bright yellow, acicular, glassy, crystals of Uranophane to around 1mm and less. Other species present.
