The facts
What dolomite actually is
Mineralogically, dolomite is dolomite — CaMg(CO₃)₂, crystallising in the trigonal system.
The colour is caused by colourless to white; Fe gives brown, Mn pale pink, Co bright pink. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.500–1.679, and the specific gravity sits near 2.84–2.86; cleavage is perfect rhombohedral.
Where dolomite comes from
The recognised sources are Eugui, Navarra, Spain, Trepča, Kosovo, Brumado, Bahia, Brazil and Tri-State district, Missouri–Kansas–Oklahoma, USA.
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 dolomite is treated
Untreated as specimens. Effervesces only weakly in cold dilute acid, unlike calcite, which is the practical field separation. Faceted dolomite is a soft collector rarity from Eugui and Brazil.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What dolomite is confused with
The usual confusions are Calcite, Magnesite, Ankerite and Siderite.
The separation is rarely a matter of opinion: refractive index 1.500–1.679 and specific gravity 2.84–2.86 settle most of it in a minute, and magnification settles the rest.
What dolomite is used for
Dolomite is bought by mineral collecting, architecture and interiors, heavy industry and metallurgy — 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, by the square metre or by the tonne.
Durability and care
Hardness 3.5–4; cleavage perfect rhombohedral. 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 dolomite costs
Indicative pricing for dolomite is Specimens $15–$1,200; faceted stones $30–$150/ct.
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 dolomite treated, and how?
Untreated as specimens. Effervesces only weakly in cold dilute acid, unlike calcite, which is the practical field separation. Faceted dolomite is a soft collector rarity from Eugui and Brazil.
Where does dolomite come from?
Eugui, Navarra, Spain, Trepča, Kosovo, Brumado, Bahia, Brazil and Tri-State district, Missouri–Kansas–Oklahoma, USA. Origin affects price, so we name the locality rather than the country on every quote.
Is dolomite 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 dolomite cost?
Indicatively Specimens $15–$1,200; faceted stones $30–$150/ct. 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 dolomite confused with?
Most often Calcite, Magnesite, Ankerite and Siderite. A refractive index of 1.500–1.679 and a specific gravity near 2.84–2.86 separate it quickly.
What is dolomite used for besides jewellery?
mineral collecting, architecture and interiors, heavy industry and metallurgy. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for dolomite?
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 dolomite