The facts
What phosgenite actually is
Phosgenite is classified as phosgenite, with the composition Pb₂(CO₃)₂Cl₂. It crystallises in the tetragonal system.
Colour comes from colourless to straw-yellow and pale pink; a lead carbonate-chloride with adamantine lustre, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 2.114–2.145. Specific gravity around 6.13. Cleavage: perfect {001} and {110}. Those three numbers separate it from most of what imitates it.
Where phosgenite comes from
Phosgenite is produced at Monteponi Mine, Iglesias, Sardinia, Italy, Laurion, Greece, Touissit, Morocco and Tsumeb, Namibia.
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 phosgenite is treated
Untreated. Historic Monteponi crystals are the benchmark and are usually fluorescent yellow under UV. Very soft, very heavy and lead-bearing; strictly a cabinet species.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What phosgenite is confused with
In the trade phosgenite is most often mistaken for, or substituted by, Cerussite, Anglesite, Calcite or Barite.
The separation is rarely a matter of opinion: refractive index 2.114–2.145 and specific gravity 6.13 settle most of it in a minute, and magnification settles the rest.
What phosgenite is used for
Demand for phosgenite comes from 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 specimen.
Durability and care
Phosgenite is 2–3 on the Mohs scale, with perfect {001} and {110} 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 phosgenite costs
As a guide, phosgenite trades around Specimens $100–$8,000; faceted stones $80–$300/ct and extremely rare.
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 phosgenite treated, and how?
Untreated. Historic Monteponi crystals are the benchmark and are usually fluorescent yellow under UV. Very soft, very heavy and lead-bearing; strictly a cabinet species.
Where does phosgenite come from?
Monteponi Mine, Iglesias, Sardinia, Italy, Laurion, Greece, Touissit, Morocco and Tsumeb, Namibia. Origin affects price, so we name the locality rather than the country on every quote.
Is phosgenite hard enough to wear every day?
Not really. At 2–3 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 phosgenite cost?
Indicatively Specimens $100–$8,000; faceted stones $80–$300/ct and extremely rare. 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 phosgenite confused with?
Most often Cerussite, Anglesite, Calcite and Barite. A refractive index of 2.114–2.145 and a specific gravity near 6.13 separate it quickly.
Related stones
Looking for phosgenite?
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 phosgenite