The facts
What microlite actually is
Mineralogically, microlite is pyrochlore supergroup — (Ca,Na)₂Ta₂O₆(O,OH,F), crystallising in the isometric system.
The colour is caused by ta with U and trace Fe gives pale yellow through brown to greenish. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.993–2.020, and the specific gravity sits near 5.50–6.40; cleavage is indistinct octahedral.
Where microlite comes from
The recognised sources are Rutherford Mine, Amelia, Virginia, USA, Alto Ligonha, Mozambique and Minas Gerais, Brazil.
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 microlite is treated
Untreated. Usually uranium-bearing and therefore metamict and mildly radioactive; the name is now a group rather than a species, so a modern report will give a specific member.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What microlite is confused with
The usual confusions are Simpsonite, Zircon and Sphalerite.
The separation is rarely a matter of opinion: refractive index 1.993–2.020 and specific gravity 5.50–6.40 settle most of it in a minute, and magnification settles the rest.
What microlite is used for
Microlite is bought by mineral collecting and heavy industry — 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 tonne.
Durability and care
Microlite is 5–5.5 on the Mohs scale, with indistinct octahedral 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 microlite costs
Indicative pricing for microlite is Faceted stones 80–400 USD/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 microlite treated, and how?
Untreated. Usually uranium-bearing and therefore metamict and mildly radioactive; the name is now a group rather than a species, so a modern report will give a specific member.
Where does microlite come from?
Rutherford Mine, Amelia, Virginia, USA, Alto Ligonha, Mozambique and Minas Gerais, Brazil. Origin affects price, so we name the locality rather than the country on every quote.
Is microlite hard enough to wear every day?
Not really. At 5–5.5 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 microlite cost?
Indicatively Faceted stones 80–400 USD/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 microlite confused with?
Most often Simpsonite, Zircon and Sphalerite. A refractive index of 1.993–2.020 and a specific gravity near 5.50–6.40 separate it quickly.
Related stones
Looking for microlite?
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 microlite