The facts
What dallasite actually is
Mineralogically, dallasite is silicified volcanic breccia — SiO₂ cementing altered basalt and epidote fragments, crystallising in the aggregate system.
The colour is caused by green from epidote and chlorite, white from chalcedony, black from altered basalt. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.53–1.55 (spot), and the specific gravity sits near 2.6–2.9; cleavage is none.
Where dallasite comes from
The recognised sources are Dallas Road, Victoria, British Columbia, Canada and Sooke, Vancouver Island, Canada.
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 dallasite is treated
Untreated; beach-collected cobbles are sawn and polished directly. A regional lapidary name in steady use on the Pacific Northwest coast.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What dallasite is confused with
The usual confusions are Ocean jasper, Unakite, Dendritic agate and Kambaba stone.
The separation is rarely a matter of opinion: refractive index 1.53–1.55 (spot) and specific gravity 2.6–2.9 settle most of it in a minute, and magnification settles the rest.
What dallasite is used for
Dallasite is bought by jewellery, mineral collecting and decorative objects — 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 carat, by the specimen or by the piece.
Durability and care
Hardness 6–7; cleavage none. 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 dallasite costs
Indicative pricing for dallasite is Cabochons 15–70 USD.
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 dallasite treated, and how?
Untreated; beach-collected cobbles are sawn and polished directly. A regional lapidary name in steady use on the Pacific Northwest coast.
Where does dallasite come from?
Dallas Road, Victoria, British Columbia, Canada and Sooke, Vancouver Island, Canada. Origin affects price, so we name the locality rather than the country on every quote.
Is dallasite 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 dallasite cost?
Indicatively Cabochons 15–70 USD. 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 dallasite confused with?
Most often Ocean jasper, Unakite, Dendritic agate and Kambaba stone. A refractive index of 1.53–1.55 (spot) and a specific gravity near 2.6–2.9 separate it quickly.
What is dallasite used for besides jewellery?
mineral collecting and decorative objects. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for dallasite?
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 dallasite