The facts
What cavansite actually is
Cavansite is classified as cavansite, with the composition Ca(V⁴⁺O)Si₄O₁₀·4H₂O. It crystallises in the orthorhombic system.
Colour comes from v⁴⁺ present as the vanadyl ion VO²⁺ — one of the textbook minerals coloured by vanadyl crystal-field transitions, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.542–1.551. Specific gravity around 2.21–2.33. Cleavage: good {010}; brittle. Those three numbers separate it from most of what imitates it.
Where cavansite comes from
Cavansite is produced at Wagholi quarries, Pune district, Maharashtra, India, Lake Owyhee State Park, Malheur County, Oregon, USA (type locality) and Chapman Quarry, Columbia County, Oregon, USA.
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 cavansite is treated
Untreated. Far too soft and brittle for wear — a pure specimen mineral, sold as vivid blue rosettes on white stilbite or heulandite matrix. Dimorphous with pentagonite.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What cavansite is confused with
In the trade cavansite is most often mistaken for, or substituted by, Pentagonite, Azurite, Shattuckite or Chrysocolla.
The separation is rarely a matter of opinion: refractive index 1.542–1.551 and specific gravity 2.21–2.33 settle most of it in a minute, and magnification settles the rest.
What cavansite is used for
Demand for cavansite comes from mineral collecting and decorative objects, 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
Cavansite is 3–4 on the Mohs scale, with good {010}; brittle 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 cavansite costs
As a guide, cavansite trades around Specimen pricing, $20–1,000 per piece.
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 cavansite treated, and how?
Untreated. Far too soft and brittle for wear — a pure specimen mineral, sold as vivid blue rosettes on white stilbite or heulandite matrix. Dimorphous with pentagonite.
Where does cavansite come from?
Wagholi quarries, Pune district, Maharashtra, India, Lake Owyhee State Park, Malheur County, Oregon, USA (type locality) and Chapman Quarry, Columbia County, Oregon, USA. Origin affects price, so we name the locality rather than the country on every quote.
Is cavansite hard enough to wear every day?
Not really. At 3–4 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 cavansite cost?
Indicatively Specimen pricing, $20–1,000 per piece. 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 cavansite confused with?
Most often Pentagonite, Azurite, Shattuckite and Chrysocolla. A refractive index of 1.542–1.551 and a specific gravity near 2.21–2.33 separate it quickly.
Related stones
Looking for cavansite?
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 cavansite