⏳ Long-term Aging & Care Timeline
fiber looseningyears
Trigger: humidity cycles
Intervention: "TV rock" fibers may separate over time in humid climates. Sealed dry case.
⚠ Safety & Handling
💧water-sensitivemoderate
"TV rock" fiber bundles slowly degrade with humidity.
Handling: Sealed case if humid climate.
Information provided in good faith. Consult local hazmat regulations for transport and disposal. Severely hazardous specimens may require special storage cabinets.
Mohs 2.5
Vickers (~) 75 HV
Knoop (~) 85 HK
Geological setting
SedimentaryEvaporite
Element composition by mass
Formula: NaCa[B₅O₆(OH)₆]·5H₂O · molar mass: 333.17 g/mol
| O | 62.43% | |
| B | 16.22% | |
| Ca | 12.03% | |
| Na | 6.9% | |
| H | 2.42% |
Computed from atomic weights (IUPAC 2021). Site-occupancy groups (Fe,Mn) split equally.
Mohs Hardness
2.5
Ulexite sits at 2.5 on the Mohs scale — can be scratched by a steel knife.
Colors:
Streak
White
White
Crystal system
Triclinic
Triclinic
BoratesBorates
TL;DR · 1 min read
Ulexite (NaCa[B₅O₆(OH)₆]·5H₂O) is a hydrated sodium-calcium borate famous for its diagnostic fiber-optic property — slabs cut perpendicular to the c-axis transmit images from one face to the other, earning it the nickname "TV rock. " Forms in arid evaporite playas of California and Chile alongside borax and colemanite.
Ulexite (NaCa[B₅O₆(OH)₆]·5H₂O) is a hydrated sodium-calcium borate famous for its diagnostic fiber-optic property — slabs cut perpendicular to the c-axis transmit images from one face to the other, earning it the nickname “TV rock.” Forms in arid evaporite playas of California and Chile alongside borax and colemanite.