The facts
What odontolite actually is
Mineralogically, odontolite is fossil mammal bone and ivory (mastodon, dinotherium) coloured blue by vivianite, then heated - not turquoise — Fluorapatite / hydroxyapatite with vivianite Fe3(PO4)2.8H2O as the colourant, crystallising in the aggregate (fibrous apatite pseudomorph) system.
The colour is caused by vivianite, converted to a blue Fe-phosphate by gentle heating during preparation. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.57-1.63, and the specific gravity sits near 3.0-3.25 (notably heavier than turquoise); cleavage is none; bone microstructure visible under magnification.
Where odontolite comes from
The recognised sources are Simorre and Gers, Midi-Pyrenees, France (the classic Miocene source), Siberia, Russia and Historic European lapidary trade, largely 12th-19th century.
Origin affects price in this material, so we name the locality on every quote rather than the country. "African" or "Asian" tells a buyer nothing.
How odontolite is treated
Historically heated to develop the blue, which is intrinsic to the material as traded. Essentially a historic gem - virtually no current production, so anything offered is antique or misidentified. Higher SG and RI than turquoise separate it immediately. Not CITES.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What odontolite is confused with
The usual confusions are Turquoise (it was sold as turquoise for centuries), Dyed howlite and Lazulite.
The separation is rarely a matter of opinion: refractive index 1.57-1.63 and specific gravity 3.0-3.25 (notably heavier than turquoise) settle most of it in a minute, and magnification settles the rest.
What odontolite is used for
Odontolite is bought by mineral collecting — and each of those trades wants a different form of the same material.
We quote each application in the unit that trade actually buys in, by the specimen.
Durability and care
Hardness 5; cleavage none; bone microstructure visible under magnification. 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 odontolite costs
Indicative pricing for odontolite is Collector market only; antique set pieces $50-800.
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 odontolite treated, and how?
Historically heated to develop the blue, which is intrinsic to the material as traded. Essentially a historic gem - virtually no current production, so anything offered is antique or misidentified. Higher SG and RI than turquoise separate it immediately. Not CITES.
Where does odontolite come from?
Simorre and Gers, Midi-Pyrenees, France (the classic Miocene source), Siberia, Russia and Historic European lapidary trade, largely 12th-19th century. Origin affects price, so we name the locality rather than the country on every quote.
Is odontolite hard enough to wear every day?
Not really. At 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 odontolite cost?
Indicatively Collector market only; antique set pieces $50-800. 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 odontolite confused with?
Most often Turquoise (it was sold as turquoise for centuries), Dyed howlite and Lazulite. A refractive index of 1.57-1.63 and a specific gravity near 3.0-3.25 (notably heavier than turquoise) separate it quickly.
Related stones
Looking for odontolite?
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 odontolite