Natural Zeolite (Clinoptilolite)

What natural Zeolite (Clinoptilolite) actually is

Natural Zeolite (Clinoptilolite) is classified as a hydrated alkali aluminosilicate with an open microporous framework, mined from altered volcanic tuff and used as a molecular sieve and ion exchanger, with the composition (Na,K,Ca)2-3Al3(Al,Si)2Si13O36.12H2O. It crystallises in the monoclinic system.

Colour comes from white, cream to pale green; the pale green is usually celadonite in the host tuff, which is also what a laboratory looks at when it is asked whether a colour is natural.

Refractive index 1.476-1.487. Specific gravity around 2.10-2.20. Cleavage: perfect in one direction. Those three numbers separate it from most of what imitates it.

Where natural Zeolite (Clinoptilolite) comes from

Natural Zeolite (Clinoptilolite) is produced at St Cloud Mine, Winston, Sierra County, New Mexico, USA, Bear River Zeolite, Preston, Idaho, USA, Gordes and Bigadic, Manisa and Balikesir, Turkiye - the largest reserves worldwide, Beli Plast and Kardzhali, Bulgaria and Tokaj Mountains, Hungary; Cabo de Gata, Almeria, Spain; Cuba.

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 natural Zeolite (Clinoptilolite) is treated

Crushed, screened and sometimes acid-activated or ammonium-exchanged; nothing that changes the mineralogy. Uses are all function-driven: water and wastewater filtration, ammonia removal in aquaculture, odour control, cat litter, animal feed additive, soil conditioner, and caesium and strontium capture - it was deployed at both Chernobyl and Fukushima for exactly that. Beware that 'zeolite' supplements sold for human consumption are poorly regulated, and some natural zeolite deposits contain fibrous erionite, which is a proven and potent carcinogen; erionite contamination is a genuine screening requirement.

Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.

What natural Zeolite (Clinoptilolite) is confused with

In the trade natural Zeolite (Clinoptilolite) is most often mistaken for, or substituted by, Synthetic zeolites (Type A, X, Y - different, engineered materials), Erionite (fibrous, carcinogenic, and a real contamination risk), Bentonite and diatomite in filtration roles or Mordenite and chabazite (other natural zeolites).

The separation is rarely a matter of opinion: refractive index 1.476-1.487 and specific gravity 2.10-2.20 settle most of it in a minute, and magnification settles the rest.

What natural Zeolite (Clinoptilolite) is used for

Demand for natural Zeolite (Clinoptilolite) comes from filtration, heavy industry, kitchen and table and cosmetics, which is why one price per carat never covers it.

We quote each application in the unit that trade actually buys in, by the tonne or by the piece.

Durability and care

Natural Zeolite (Clinoptilolite) is 3.5-4 on the Mohs scale, with perfect in one direction 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 natural Zeolite (Clinoptilolite) costs

As a guide, natural Zeolite (Clinoptilolite) trades around $60-300 per tonne bulk depending on grade and sizing; specialty and pharmaceutical grades far higher.

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.

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