Ulexite
Mineral NaCaB5O6(OH)6·5H2O
Also called TV rock, Television stone, and Cotton balls
Take care.
- Damaged by water: Keep it dry: don't wash it, and keep it out of damp places.
About it
Silky white fibres; slabs cut across the fibres carry an image to the top surface like fibre optics, hence 'TV rock'. Also forms 'cotton ball' nodules; Boron, California, and Turkey are the main sources.
- Type
- Mineral
- Group
- Borate
- Formula
- NaCaB5O6(OH)6·5H2O
- Hardness (Mohs)
- 2.5
- Specific gravity
- 1.95–1.96
- Streak
- white
- Lustre
- vitreous (glassy), silky
- Crystal system
- Triclinic
- Colours
- white, colourless
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction; fibrous
Typical values: real specimens vary. For more, see mindat.org.