The facts
What charnockite actually is
The species behind charnockite is orthopyroxene-bearing granitoid, formed at granulite-facies conditions - a distinct petrological rock type, not a trade name, Quartz, perthitic feldspar, orthopyroxene (hypersthene), garnet and magnetite; it forms in the aggregate system.
Greasy blue-green tone from hypersthene and from the bluish quartz typical of granulites 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 specific gravity of about 2.70-2.90, with feldspar and pyroxene cleavage cleavage.
Where charnockite comes from
Commercial material comes from Pallavaram and St Thomas Mount, Chennai, Tamil Nadu, India - the type locality, named after Job Charnock's tombstone, Kerala and Karnataka, India, Sri Lanka (Highland Complex) and Enderby Land, Antarctica; Norway and Madagascar.
Different localities give different colour and different clarity, and the trade prices them differently. We state which one.
How charnockite is treated
Untreated as dimension stone; resin-backed as slabs. Sold in the Indian stone trade under commercial names rather than as charnockite, so the petrological name rarely reaches the buyer. A large share of southern Indian temple architecture is built from it. Not CITES.
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 charnockite is confused with
Watch for Granite and gneiss, Gabbro and Enderbite and mangerite (related granulite rocks) — these are what turn up sold under this name.
Because the material is opaque, refractive index is no help. Specific gravity around 2.70-2.90, hardness of 6-7, streak and magnification do the work instead.
What charnockite is used for
The trades that buy charnockite are architecture and interiors, heavy industry, decorative objects and 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 square metre, by the tonne or by the piece.
Durability and care
Hardness 6-7; cleavage feldspar and pyroxene cleavage. That combination decides what it can safely be set into.
With no cleavage plane to worry about, the practical limit is abrasion rather than breakage, and it takes daily wear well.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What charnockite costs
Expect roughly $25-90 per square foot as dimension stone, 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 charnockite treated, and how?
Untreated as dimension stone; resin-backed as slabs. Sold in the Indian stone trade under commercial names rather than as charnockite, so the petrological name rarely reaches the buyer. A large share of southern Indian temple architecture is built from it. Not CITES.
Where does charnockite come from?
Pallavaram and St Thomas Mount, Chennai, Tamil Nadu, India - the type locality, named after Job Charnock's tombstone, Kerala and Karnataka, India, Sri Lanka (Highland Complex) and Enderby Land, Antarctica; Norway and Madagascar. Origin affects price, so we name the locality rather than the country on every quote.
Is charnockite hard enough to wear every day?
Yes. At 6-7 on the Mohs scale with no cleavage plane, it handles daily wear well. The practical limit is gradual abrasion rather than chipping.
How much does charnockite cost?
Indicatively $25-90 per square foot as dimension stone. 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 charnockite confused with?
Most often Granite and gneiss, Gabbro and Enderbite and mangerite (related granulite rocks). Since the material is opaque, separation relies on specific gravity near 2.70-2.90, hardness and magnification.
What is charnockite used for besides jewellery?
architecture and interiors, heavy industry, decorative objects and mineral collecting. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for charnockite?
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 charnockite