The facts
What anthophyllite actually is
Anthophyllite is classified as amphibole group (orthoamphibole), with the composition ☐Mg₂Mg₅Si₈O₂₂(OH)₂. It crystallises in the orthorhombic system.
Colour comes from fe²⁺ gives the clove-brown to greenish tones, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.603–1.690. Specific gravity around 2.90–3.50. Cleavage: perfect prismatic in two directions at about 55°. Those three numbers separate it from most of what imitates it.
Where anthophyllite comes from
Anthophyllite is produced at Kongsberg, Buskerud, Norway, Paakkila, Outokumpu, Finland and Ekaterinburg, Ural Mountains, Russia.
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 anthophyllite is treated
Untreated. Asbestiform anthophyllite is a regulated carcinogen and must not be worked dry; only massive non-fibrous material should be cut. Nuummite is an anthophyllite–gedrite rock and is already a separate trade material.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What anthophyllite is confused with
In the trade anthophyllite is most often mistaken for, or substituted by, Gedrite, Enstatite or Bronzite.
The separation is rarely a matter of opinion: refractive index 1.603–1.690 and specific gravity 2.90–3.50 settle most of it in a minute, and magnification settles the rest.
What anthophyllite is used for
Demand for anthophyllite comes from mineral collecting, 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.
Durability and care
Hardness 5.5–6; cleavage perfect prismatic in two directions at about 55°. That combination decides what it can safely be set into.
Hardness is not the whole story. Perfect cleavage means the stone can split cleanly if struck along the wrong plane, whatever its Mohs number, so a protective setting matters more here than the hardness suggests.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What anthophyllite costs
As a guide, anthophyllite trades around Specimens 10–60 USD; faceted stones under 50 USD/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 anthophyllite treated, and how?
Untreated. Asbestiform anthophyllite is a regulated carcinogen and must not be worked dry; only massive non-fibrous material should be cut. Nuummite is an anthophyllite–gedrite rock and is already a separate trade material.
Where does anthophyllite come from?
Kongsberg, Buskerud, Norway, Paakkila, Outokumpu, Finland and Ekaterinburg, Ural Mountains, Russia. Origin affects price, so we name the locality rather than the country on every quote.
Is anthophyllite hard enough to wear every day?
With care. It is 5.5–6 on the Mohs scale, which is hard enough, but perfect prismatic in two directions at about 55° cleavage means it can split if struck at the wrong angle. Use a protective setting and avoid ultrasonic cleaning.
How much does anthophyllite cost?
Indicatively Specimens 10–60 USD; faceted stones under 50 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 anthophyllite confused with?
Most often Gedrite, Enstatite and Bronzite. A refractive index of 1.603–1.690 and a specific gravity near 2.90–3.50 separate it quickly.
Related stones
Looking for anthophyllite?
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 anthophyllite