Hydrokenopyrochlore
Hydrokenopyrochlore is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula ( ,Sb³⁺,Na)₂Nb₂O₆·H₂O.
It crystallizes in the cubic crystal system (space group Fd-3m). It is a member of the Pyrochlore-Pyrochlore structural group.
Key properties: specific gravity 5.984; White streak; Resinous luster.
IMA symbol Hkpcl, IMA status: approved, named in 2017.
From a Li-Cs-Ta-type pegmatite intruded into dolomitic marble.
It is found associated with Quartz, orthoclase, Li-rich mica, hübnerite, a heftetjernite-like mineral, stibiotantalite, tourmaline.
The first prefix, hydro, indicates dominant H2O at the Y site, the second prefix, keno, indicates the dominant vacancy in the A site of a member of the pyrochlore subgroup.