The facts
What monazite actually is
Monazite is classified as rare-earth phosphate, with the composition (Ce,La,Nd,Th)PO₄. It crystallises in the monoclinic system.
Colour comes from yellow to reddish brown from Ce, La and Nd; Nd gives a distinctive sharp absorption spectrum, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.796–1.841. Specific gravity around 4.80–5.50. Cleavage: distinct in one direction. Those three numbers separate it from most of what imitates it.
Where monazite comes from
Monazite is produced at Ambolotarakely, Analamanga, Madagascar, Zagi Mountain, Khyber Pakhtunkhwa, Pakistan and Minas Gerais, Brazil.
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 monazite is treated
Untreated but thorium-bearing and therefore radioactive; it is the principal ore of light rare earths and is regulated as a radioactive material in several countries. Not a stone to wear.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What monazite is confused with
In the trade monazite is most often mistaken for, or substituted by, Xenotime, Zircon, Sphene or Titanite.
The separation is rarely a matter of opinion: refractive index 1.796–1.841 and specific gravity 4.80–5.50 settle most of it in a minute, and magnification settles the rest.
What monazite is used for
Demand for monazite comes from mineral collecting, heavy industry and technical and precision components, 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, by the tonne or by the piece.
Durability and care
Hardness 5–5.5; cleavage distinct in one direction. That combination decides what it can safely be set into.
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 monazite costs
As a guide, monazite trades around Faceted stones 40–200 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 monazite treated, and how?
Untreated but thorium-bearing and therefore radioactive; it is the principal ore of light rare earths and is regulated as a radioactive material in several countries. Not a stone to wear.
Where does monazite come from?
Ambolotarakely, Analamanga, Madagascar, Zagi Mountain, Khyber Pakhtunkhwa, Pakistan and Minas Gerais, Brazil. Origin affects price, so we name the locality rather than the country on every quote.
Is monazite 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 monazite cost?
Indicatively Faceted stones 40–200 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 monazite confused with?
Most often Xenotime, Zircon, Sphene and Titanite. A refractive index of 1.796–1.841 and a specific gravity near 4.80–5.50 separate it quickly.
What is monazite used for besides jewellery?
mineral collecting, heavy industry and technical and precision components. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for monazite?
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 monazite