The facts
What quahog Pearl actually is
The species behind quahog Pearl is non-nacreous concretion from the hard clam Mercenaria mercenaria, Aragonite / calcite CaCO3 with conchiolin; it forms in the aggregate system.
Purple pigment from the shell's interior colour band is responsible for the colour — and the chromophore, not the name, is what decides whether a colour is stable.
On the instruments it reads a refractive index of 1.50-1.68 and a specific gravity of about 2.65-2.85, with none cleavage.
Where quahog Pearl comes from
Commercial material comes from Cape Cod and Buzzards Bay, Massachusetts, USA, Narragansett Bay, Rhode Island, USA and Long Island Sound, New York, USA.
Different localities give different colour and different clarity, and the trade prices them differently. We state which one.
How quahog Pearl is treated
Not CITES. Cannot be cultured commercially. Found incidentally by shellfishermen, so supply is a by-product of the food industry - which makes provenance easy and fakery relatively uncommon. Colour is light-sensitive.
We state the treatment on every stone, including when the honest answer is that it cannot be determined. A treatment disclosed is a fact; a treatment discovered later is a refund.
What quahog Pearl is confused with
Watch for Dyed freshwater pearls, Purple shell beads and Amethyst beads — these are what turn up sold under this name.
The separation is rarely a matter of opinion: refractive index 1.50-1.68 and specific gravity 2.65-2.85 settle most of it in a minute, and magnification settles the rest.
What quahog Pearl is used for
The trades that buy quahog Pearl are jewellery and mineral collecting. They do not want the same thing, and they do not pay in the same unit.
We quote each application in the unit that trade actually buys in, by the carat or by the specimen.
Durability and care
Quahog Pearl is 3.5-4 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 quahog Pearl costs
Expect roughly $100-2,000 per carat; large well-formed purples with flame structure higher, depending on quality.
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 quahog Pearl treated, and how?
Not CITES. Cannot be cultured commercially. Found incidentally by shellfishermen, so supply is a by-product of the food industry - which makes provenance easy and fakery relatively uncommon. Colour is light-sensitive.
Where does quahog Pearl come from?
Cape Cod and Buzzards Bay, Massachusetts, USA, Narragansett Bay, Rhode Island, USA and Long Island Sound, New York, USA. Origin affects price, so we name the locality rather than the country on every quote.
Is quahog Pearl hard enough to wear every day?
Not really. At 3.5-4 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 quahog Pearl cost?
Indicatively $100-2,000 per carat; large well-formed purples with flame structure higher. 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 quahog Pearl confused with?
Most often Dyed freshwater pearls, Purple shell beads and Amethyst beads. A refractive index of 1.50-1.68 and a specific gravity near 2.65-2.85 separate it quickly.
Related stones
Looking for quahog pearl?
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 quahog pearl