The facts
What kyanite actually is
Kyanite is classified as kyanite, with the composition Al₂SiO₅. It crystallises in the triclinic system.
Colour comes from iron and titanium, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.710–1.734. Specific gravity around 3.53–3.70. Cleavage: perfect, two directions. Those three numbers separate it from most of what imitates it.
Where kyanite comes from
Kyanite is produced at Nepal, Brazil, Kenya and Switzerland.
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.
Is kyanite treated?
None normally.
That makes disclosure simple: there is nothing to declare. It also means a seller offering a "treated" version of this material is offering something else.
What kyanite is confused with
In the trade kyanite is most often mistaken for, or substituted by, Sapphire, Tanzanite or Indicolite.
The separation is rarely a matter of opinion: refractive index 1.710–1.734 and specific gravity 3.53–3.70 settle most of it in a minute, and magnification settles the rest.
What kyanite is used for
Demand for kyanite comes from jewellery, mineral collecting and refractories, which is why one price per carat never covers it.
We quote each application in the unit that trade actually buys in, by the carat, by the specimen or by the tonne.
Durability and care
Hardness 4.5–7 — different along different axes; cleavage perfect, two directions. That combination decides what it can safely be set into.
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 kyanite costs
As a guide, kyanite trades around $10–300/ct.
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 kyanite treated?
None normally.
Where does kyanite come from?
Nepal, Brazil, Kenya and Switzerland. Origin affects price, so we name the locality rather than the country on every quote.
Is kyanite hard enough to wear every day?
Not really. At 4.5–7 — different along different axes 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 kyanite cost?
Indicatively $10–300/ct. 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 kyanite confused with?
Most often Sapphire, Tanzanite and Indicolite. A refractive index of 1.710–1.734 and a specific gravity near 3.53–3.70 separate it quickly.
What is kyanite used for besides jewellery?
mineral collecting and refractories. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for kyanite?
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 kyanite