coronadite

coronadite

[‚kȯr·ə′nä‚dīt]
(mineralogy)
Pb(Mn2+,Mn4+)8O16 A black mineral consisting of a lead and manganese oxide, occurring in massive form with fibrous structure; an important constituent of manganese ore.
References in periodicals archive ?
Coronadite was found in the Snake Pit adit by the authors as brownish black spheres and botryoidal masses in association with tabular, yellow wulfenite crystals.
Specimens of coronadite from the Snake Pit mine occur with crystals of what appears to be a clay mineral.
Typical associations include plattnerite, coronadite and wulfenite.
Recently, very minor hydro-hetaerolite and coronadite have also been identified (Ryback and Moreton, 1993).
Additional minerals present include zircon, gahnite, minor spessartine, hectorite and coronadite, and secondary phosphates fluorapatite, eosphorite and crandallite.
The outer surfaces of the hthiophilite show varying degrees of alteration, and appear pale to dark brown due to minute films of coronadite and/or hectorite.
Albite Beryl Covellite Gahnite Fluorapatite Digenite Lithiophilite Gahnite Galena Spessartine Manganocolumbite Hessite Triplite Microcline Triploidite Muscovite Secondary Triphylite Pyrochlore Minerals UK-1 Quartz Chrysocolla Zircon Rutile (niobian) Malachite Schorl UK-2 Secondary Phosphates Spessartine Crandallite Spodumene Eosphorite Uranmicrolite Fluorapatite Uranpyrochlore Zircon Secondary Minerals Coronadite Hectorite
Coronadite is occasionally also seen replacing mimetite crystals.
The most impressive specimens have orange to orange-red crystals to 5 mm richly scattered on coronadite and quartz-rich rocks.
Tabular, yellow and bright orange to orange-red crystals occur scattered on coronadite matrix.