The facts
What merlinite actually is
Merlinite is classified as chalcedony or common opal with manganese oxide dendrites, with the composition SiO₂ with Mn-oxide dendrites. It crystallises in the cryptocrystalline aggregate system.
Colour comes from black manganese oxide dendrites in white to grey silica; the dendrites are surface-fed mineral growths, not fossils, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.48–1.54 (variable). Specific gravity around 2.2–2.6. Cleavage: none. Those three numbers separate it from most of what imitates it.
Where merlinite comes from
Merlinite is produced at Socorro County, New Mexico, USA and Sierra County, New Mexico, USA.
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 merlinite is treated
Untreated. A lapidary trade name rather than a species; the same material is sold honestly as dendritic agate or dendritic opal. Treat 'mystic merlinite' and similar as marketing overlays on ordinary dendritic rock.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What merlinite is confused with
In the trade merlinite is most often mistaken for, or substituted by, Dendritic agate, Moss agate or Turritella agate.
The separation is rarely a matter of opinion: refractive index 1.48–1.54 (variable) and specific gravity 2.2–2.6 settle most of it in a minute, and magnification settles the rest.
What merlinite is used for
Demand for merlinite comes from jewellery, mineral collecting, decorative objects and wellness and body care, which is why one price per carat never covers it.
We quote each application in the unit that trade actually buys in, by the carat, by the specimen or by the piece.
Durability and care
Hardness 6–7; cleavage none. That combination decides what it can safely be set into.
With no cleavage plane to worry about, the practical limit is abrasion rather than breakage, and it takes daily wear well.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What merlinite costs
As a guide, merlinite trades around Cabochons 10–60 USD.
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 merlinite treated, and how?
Untreated. A lapidary trade name rather than a species; the same material is sold honestly as dendritic agate or dendritic opal. Treat 'mystic merlinite' and similar as marketing overlays on ordinary dendritic rock.
Where does merlinite come from?
Socorro County, New Mexico, USA and Sierra County, New Mexico, USA. Origin affects price, so we name the locality rather than the country on every quote.
Is merlinite hard enough to wear every day?
Yes. At 6–7 on the Mohs scale with no cleavage plane, it handles daily wear well. The practical limit is gradual abrasion rather than chipping.
How much does merlinite cost?
Indicatively Cabochons 10–60 USD. 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 merlinite confused with?
Most often Dendritic agate, Moss agate and Turritella agate. A refractive index of 1.48–1.54 (variable) and a specific gravity near 2.2–2.6 separate it quickly.
What is merlinite used for besides jewellery?
mineral collecting, decorative objects and wellness and body care. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for merlinite?
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 merlinite