Circular aggregates of the rare mineral meurigite-Na on matrix from the type locality (Silver Coin Mine, Valmy, Nevada, United States of America). Meurigite-Na has only been found in 5 localities worldwide. — Photo: David Hospital · CC BY-SA 4.0
Meurigite-Na
Meurigite-Na is an IMA-recognized mineral species in the phosphate class, with the chemical formula [Na(H₂O)₂.₅][Fe³⁺₈(PO₄)₆(OH)₇(H₂O)₄].
It crystallizes in the monoclinic crystal system (space group C2/c). It is a member of the Phosphofibrite structural group.
Key properties: Mohs hardness 3; specific gravity 2.94; White streak; Silky luster; optically biaxial.
IMA symbol Meu-Na, IMA status: approved, named in 2007.
A late-stage, low-temperature, secondary mineral in complex phosphate assemblages rich in Fe3+ and Na.
It is found associated with Turquoise, intergrown kidwellite/lipscombite, crandallite, goethite.
The mineral was named to honor Professor John Meurig Thomas (b. 1932), crystal chemist, University of Cambridge, Cambridge, England. The suffix, Na, indicates dominant sodium rather than potassium.