The facts
What haüyne actually is
Mineralogically, haüyne is haüyne (sodalite group) — (Na,Ca)₄₋₈Al₆Si₆(O,S)₂₄(SO₄,Cl)₁₋₂, crystallising in the cubic system.
The colour is caused by not firmly established in the gemmological literature; by structural analogy with lapis and sodalite it belongs to the sulphur-radical-in-cage family, but no source consulted confirms it for haüyne specifically. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.494–1.509 (isotropic), and the specific gravity sits near 2.40–2.50; cleavage is distinct to perfect dodecahedral — sources disagree on the count of directions; in practice a fragile stone.
Where haüyne comes from
The recognised sources are Laacher See and Niedermendig, Eifel, Germany, Mount Vesuvius, Italy and Mogok, Myanmar.
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 haüyne is treated
Paraffin wax is reported as a fracture sealant on some material, though other sources say no treatment at all. Faceted stones are almost always under 1–2 ct, and the Eifel is the only consistent source of transparent facetable blue. Fluorescence is colour-dependent: pale material glows orange-pink under long-wave UV, saturated dark blue is usually inert.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What haüyne is confused with
The usual confusions are Lazurite, Sodalite, Apatite, Blue spinel and Benitoite.
The separation is rarely a matter of opinion: refractive index 1.494–1.509 (isotropic) and specific gravity 2.40–2.50 settle most of it in a minute, and magnification settles the rest.
What haüyne is used for
Haüyne is bought by mineral collecting and jewellery — 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 or by the carat.
Durability and care
Haüyne is 5–6 on the Mohs scale, with distinct to perfect dodecahedral — sources disagree on the count of directions; in practice a fragile stone 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 haüyne costs
Indicative pricing for haüyne is $200–2,000/ct for clean faceted Eifel material.
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 haüyne treated, and how?
Paraffin wax is reported as a fracture sealant on some material, though other sources say no treatment at all. Faceted stones are almost always under 1–2 ct, and the Eifel is the only consistent source of transparent facetable blue. Fluorescence is colour-dependent: pale material glows orange-pink under long-wave UV, saturated dark blue is usually inert.
Where does haüyne come from?
Laacher See and Niedermendig, Eifel, Germany, Mount Vesuvius, Italy and Mogok, Myanmar. Origin affects price, so we name the locality rather than the country on every quote.
Is haüyne hard enough to wear every day?
Not really. At 5–6 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 haüyne cost?
Indicatively $200–2,000/ct for clean faceted Eifel material. 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 haüyne confused with?
Most often Lazurite, Sodalite, Apatite, Blue spinel and Benitoite. A refractive index of 1.494–1.509 (isotropic) and a specific gravity near 2.40–2.50 separate it quickly.
Related stones
Looking for haüyne?
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 haüyne