Mineralpedia Details for Ulexite
Ulexite
Named to honor George Ludwig Ulex, the German chemist who was the first to accurately analyze the mineral. This widespread mineral occurs most typically in playa and salt-marsh deposits that form in arid regions. Ulexite can be found in the surrounding bedding from such deposits with the boron source coming from near-by hot springs. Certain occurrences of these types of deposit circumstances can contain up to one billion tons of this mineral. Parallel masses of these fibrous crystals have natural fiber optic properties, allowing for light and even images to be transferred from one end of the crystal to the other. This property is why the mineral is occasionally called the “TV rock” or “television stone.” Ulexite is somewhat soluble in water. Under long-wave and short-wave ultraviolet light, Ulexite may fluoresce a yellow, yellow-green, cream or white. In some cases it is also phosphorescent.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/ulexite.pdf
- Formula
- NaCaB5O6(OH)6ยท5H2O
- Crystal System
- Triclinic
- Crystal Habit
- Acicular, Fibrous, Capillary
- Cleavage
- Perfect, Perfect, None
- Luster
- Chatoyant
- Color
- colorless, white
- Streak
- white
- Class
- Triclinic - Pinacoidal
- Fracture
- Brittle
- Hardness
- 2.5
- WebMineral
- View Ulexite
- Mindat
- View Ulexite
Ulexite from Boron, Kern Co., California, United States
An excellent specimen showing the fibrous nature of Ulexite used in fiber optics. Also called "TV rock" Ulexite as the remarkable property of transferring light through its fibers by the refraction of light even when bent.
