The facts
What carletonite actually is
The species behind carletonite is potassium-sodium-calcium silicate, KNa₄Ca₄Si₈O₁₈(CO₃)₄(F,OH)·H₂O; it forms in the tetragonal system.
A genuine blue whose origin is not fully resolved; sulphur-related colour centres are the usual explanation is responsible for the colour — and the chromophore, not the name, is what decides whether a colour is stable.
On the instruments it reads a refractive index of 1.517–1.521 and a specific gravity of about 2.45, with perfect basal cleavage.
Where carletonite comes from
Commercial material comes from Poudrette Quarry, Mont Saint-Hilaire, Québec, Canada.
That is the whole list. A single source makes supply fragile and makes any claim of a second origin worth questioning.
How carletonite is treated
Untreated. Known from a single quarry, which is intermittently closed to collecting; prices reflect that. Soft with perfect cleavage, so faceted stones are fragile collector pieces.
We state the treatment on every stone, including when the honest answer is that it cannot be determined. A treatment disclosed is a fact; a treatment discovered later is a refund.
What carletonite is confused with
Watch for Apatite, Fluorite, Sodalite and Aquamarine — these are what turn up sold under this name.
The separation is rarely a matter of opinion: refractive index 1.517–1.521 and specific gravity 2.45 settle most of it in a minute, and magnification settles the rest.
What carletonite is used for
The trades that buy carletonite are mineral collecting. They do not want the same thing, and they do not pay in the same unit.
We quote each application in the unit that trade actually buys in, by the specimen.
Durability and care
Carletonite is 4–4.5 on the Mohs scale, with perfect basal 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 carletonite costs
Expect roughly Specimens 200–5,000 USD; faceted stones 500–2,000 USD/ct, depending on quality.
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 carletonite treated, and how?
Untreated. Known from a single quarry, which is intermittently closed to collecting; prices reflect that. Soft with perfect cleavage, so faceted stones are fragile collector pieces.
Where does carletonite come from?
Poudrette Quarry, Mont Saint-Hilaire, Québec, Canada. That is the only commercial source.
Is carletonite hard enough to wear every day?
Not really. At 4–4.5 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 carletonite cost?
Indicatively Specimens 200–5,000 USD; faceted stones 500–2,000 USD/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 carletonite confused with?
Most often Apatite, Fluorite, Sodalite and Aquamarine. A refractive index of 1.517–1.521 and a specific gravity near 2.45 separate it quickly.
Related stones
Looking for carletonite?
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 carletonite