The facts
What aurichalcite actually is
Mineralogically, aurichalcite is aurichalcite — (Zn,Cu)₅(CO₃)₂(OH)₆, crystallising in the monoclinic system.
The colour is caused by cu²⁺ in a zinc-dominant carbonate, giving pale sky-blue to blue-green. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.654–1.744, and the specific gravity sits near 3.64–4.20; cleavage is perfect {010}.
Where aurichalcite comes from
The recognised sources are 79 Mine, Gila County, Arizona, USA, Ojuela Mine, Mapimí, Durango, Mexico, Tsumeb, Namibia and Laurion, Greece.
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 aurichalcite is treated
Untreated. The silky acicular sprays are so soft and fragile that specimens must never be washed or brushed; some cabochon material is really aurichalcite included in chalcedony or calcite, which is a legitimate composite but should be described as such.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What aurichalcite is confused with
The usual confusions are Rosasite, Hemimorphite, Chrysocolla and Smithsonite.
The separation is rarely a matter of opinion: refractive index 1.654–1.744 and specific gravity 3.64–4.20 settle most of it in a minute, and magnification settles the rest.
What aurichalcite is used for
Aurichalcite 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
Aurichalcite is 1–2 on the Mohs scale, with perfect {010} 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 aurichalcite costs
Indicative pricing for aurichalcite is Specimens $25–$600.
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 aurichalcite treated, and how?
Untreated. The silky acicular sprays are so soft and fragile that specimens must never be washed or brushed; some cabochon material is really aurichalcite included in chalcedony or calcite, which is a legitimate composite but should be described as such.
Where does aurichalcite come from?
79 Mine, Gila County, Arizona, USA, Ojuela Mine, Mapimí, Durango, Mexico, Tsumeb, Namibia and Laurion, Greece. Origin affects price, so we name the locality rather than the country on every quote.
Is aurichalcite hard enough to wear every day?
Not really. At 1–2 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 aurichalcite cost?
Indicatively Specimens $25–$600. 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 aurichalcite confused with?
Most often Rosasite, Hemimorphite, Chrysocolla and Smithsonite. A refractive index of 1.654–1.744 and a specific gravity near 3.64–4.20 separate it quickly.
Related stones
Looking for aurichalcite?
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 aurichalcite