The facts
What bixbyite actually is
Bixbyite is classified as bixbyite, with the composition (Mn,Fe)₂O₃. It crystallises in the cubic system.
Colour comes from mn³⁺ and Fe³⁺ in an opaque oxide; black with submetallic lustre, which is also what a laboratory looks at when it is asked whether a colour is natural.
Specific gravity around 4.95. Cleavage: indistinct octahedral {111}. Those three numbers separate it from most of what imitates it.
Where bixbyite comes from
Bixbyite is produced at Thomas Range (Topaz Mountain), Juab County, Utah, USA and Postmasburg, South Africa.
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 bixbyite is treated
Untreated. Sharp lustrous cubes from the Thomas Range rhyolite, often associated with red beryl and topaz, are the classic material. Not to be confused with bixbite, an obsolete name for red beryl.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What bixbyite is confused with
In the trade bixbyite is most often mistaken for, or substituted by, Magnetite, Hausmannite or Braunite.
Because the material is opaque, refractive index is no help. Specific gravity around 4.95, hardness of 6–6.5, streak and magnification do the work instead.
What bixbyite is used for
Demand for bixbyite 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
Bixbyite is 6–6.5 on the Mohs scale, with indistinct octahedral {111} cleavage.
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 bixbyite costs
As a guide, bixbyite trades around Thomas Range crystals $40–$1,500.
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 bixbyite treated, and how?
Untreated. Sharp lustrous cubes from the Thomas Range rhyolite, often associated with red beryl and topaz, are the classic material. Not to be confused with bixbite, an obsolete name for red beryl.
Where does bixbyite come from?
Thomas Range (Topaz Mountain), Juab County, Utah, USA and Postmasburg, South Africa. Origin affects price, so we name the locality rather than the country on every quote.
Is bixbyite hard enough to wear every day?
Yes. At 6–6.5 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 bixbyite cost?
Indicatively Thomas Range crystals $40–$1,500. 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 bixbyite confused with?
Most often Magnetite, Hausmannite and Braunite. Since the material is opaque, separation relies on specific gravity near 4.95, hardness and magnification.
Related stones
Looking for bixbyite?
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 bixbyite