Panethite
A rare sodium-calcium-magnesium phosphate known only from the Dayton meteorite.
Intro adapted from Wikipedia (CC BY-SA).
Panethite is an IMA-recognized mineral species in the phosphate class, with the chemical formula (Na,Ca,K)₁₋ₓ(Mg,Fe²⁺,Mn)PO₄.
It crystallizes in the monoclinic crystal system (space group P2_1/n).
Key properties: specific gravity 2.9–3; optically biaxial.
IMA symbol Pne, IMA status: approved, named in 1966.
Found as a very rare mineral in phosphate nodules in an iron meteorite.
It is found associated with Brianite, whitlockite, albite, enstatite, schreibersite, kamacite, taenite, graphite, sphalerite, troilite.
The mineral was named to honor Professor Friedrich Adolf Paneth (1887–1958), Austrian chemist, Director of the Max Planck Institute for Chemistry, Mainz, Germany.