The facts
What mahogany Obsidian actually is
Mahogany Obsidian is classified as obsidian with red-brown bands and patches produced by oxidised iron inclusions, with the composition Rhyolitic glass with hematite and limonite staining. It crystallises in the amorphous system.
Colour comes from hematite and iron oxide for the mahogany bands, magnetite nanoparticles for the black, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.48-1.51. Specific gravity around 2.30-2.50. Cleavage: none. Those three numbers separate it from most of what imitates it.
Where mahogany Obsidian comes from
Mahogany Obsidian is produced at Glass Buttes and Lake County, Oregon, USA, Davis Creek and Modoc County, California, USA, Nevada, USA and Jalisco, Mexico.
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 mahogany Obsidian is treated
Untreated. A genuine natural material, though the name is also applied loosely to any brown-banded obsidian. Cheap and abundant, so imitation is rare. Not CITES.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What mahogany Obsidian is confused with
In the trade mahogany Obsidian is most often mistaken for, or substituted by, Ordinary banded obsidian, Slag glass with brown streaks or Brown chalcedony.
The separation is rarely a matter of opinion: refractive index 1.48-1.51 and specific gravity 2.30-2.50 settle most of it in a minute, and magnification settles the rest.
What mahogany Obsidian is used for
Demand for mahogany Obsidian comes from jewellery, carving and sculpture, decorative objects and 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 carat, by the block or by the piece.
Durability and care
Mahogany Obsidian is 5-5.5 on the Mohs scale, with none 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 mahogany Obsidian costs
As a guide, mahogany Obsidian trades around $1-4 per kilogram rough; cabochons $5-25.
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 mahogany Obsidian treated, and how?
Untreated. A genuine natural material, though the name is also applied loosely to any brown-banded obsidian. Cheap and abundant, so imitation is rare. Not CITES.
Where does mahogany Obsidian come from?
Glass Buttes and Lake County, Oregon, USA, Davis Creek and Modoc County, California, USA, Nevada, USA and Jalisco, Mexico. Origin affects price, so we name the locality rather than the country on every quote.
Is mahogany Obsidian hard enough to wear every day?
Not really. At 5-5.5 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 mahogany Obsidian cost?
Indicatively $1-4 per kilogram rough; cabochons $5-25. 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 mahogany Obsidian confused with?
Most often Ordinary banded obsidian, Slag glass with brown streaks and Brown chalcedony. A refractive index of 1.48-1.51 and a specific gravity near 2.30-2.50 separate it quickly.
What is mahogany Obsidian used for besides jewellery?
carving and sculpture, decorative objects and mineral collecting. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for mahogany obsidian?
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 mahogany obsidian