The facts
What ulexite actually is
Ulexite is classified as ulexite, with the composition NaCaB₅O₆(OH)₆·5H₂O. It crystallises in the triclinic system.
Colour comes from colourless to white; the fibrous aggregate is the whole point, not the colour, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.491–1.520. Specific gravity around 1.95–1.96. Cleavage: perfect {010}. Those three numbers separate it from most of what imitates it.
Where ulexite comes from
Ulexite is produced at Boron and Death Valley, California, USA, Salar del Hombre Muerto and Tincalayu, Salta, Argentina, Suckow Mine, Kramer district, California, USA and Iquique, Chile.
The locality is part of the description, not a footnote — two stones of the same weight from two of these places are not the same stone.
How ulexite is treated
Untreated, but the polished 'TV rock' slabs that project an image from the back face are cut perpendicular to the fibres, and the effect is natural fibre-optic transmission, not a treatment. Water-soluble and very soft; never wash. Some 'ulexite' plates sold online are resin-backed.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What ulexite is confused with
In the trade ulexite is most often mistaken for, or substituted by, Satin spar gypsum, Selenite, Colemanite or Fibre-optic glass.
The separation is rarely a matter of opinion: refractive index 1.491–1.520 and specific gravity 1.95–1.96 settle most of it in a minute, and magnification settles the rest.
What ulexite is used for
Demand for ulexite comes from mineral collecting, decorative objects and technical and precision components, which is why one price per carat never covers it.
We quote each application in the unit that trade actually buys in, by the specimen or by the piece.
Durability and care
Ulexite is 2–2.5 on the Mohs scale, with perfect {010} cleavage.
Below about 5.5 a stone will be scratched by ordinary household dust, which is largely quartz. That does not make it unusable — it makes it a pendant, an earring or an object rather than a ring worn every day.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What ulexite costs
As a guide, ulexite trades around Polished TV-rock plates $5–$50; crystallised specimens $20–$300.
That is a range, not a quote. Colour, size, clarity, cut and origin move the figure a long way inside it, and the only honest price is one given against a specific stone. Send us what you need and we will price it.
Questions
Is ulexite treated, and how?
Untreated, but the polished 'TV rock' slabs that project an image from the back face are cut perpendicular to the fibres, and the effect is natural fibre-optic transmission, not a treatment. Water-soluble and very soft; never wash. Some 'ulexite' plates sold online are resin-backed.
Where does ulexite come from?
Boron and Death Valley, California, USA, Salar del Hombre Muerto and Tincalayu, Salta, Argentina, Suckow Mine, Kramer district, California, USA and Iquique, Chile. Origin affects price, so we name the locality rather than the country on every quote.
Is ulexite hard enough to wear every day?
Not really. At 2–2.5 on the Mohs scale it is softer than the quartz dust in ordinary household dirt, so it scratches with wear. It suits pendants, earrings and objects better than a daily ring.
How much does ulexite cost?
Indicatively Polished TV-rock plates $5–$50; crystallised specimens $20–$300. Colour, size, clarity and origin move the price a long way within that, so treat it as a range and ask for a quote against a specific stone.
What is ulexite confused with?
Most often Satin spar gypsum, Selenite, Colemanite and Fibre-optic glass. A refractive index of 1.491–1.520 and a specific gravity near 1.95–1.96 separate it quickly.
What is ulexite used for besides jewellery?
mineral collecting, decorative objects and technical and precision components. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for ulexite?
Tell us the size, the quality and what it is for. We source it, photograph it and quote it — with the locality named.
Ask about ulexite