Aci Castello, Etna Volcanic Complex, Catania Province, Sicily, Italy
Chemical Formula: (Ca0.5,Na,K)4[Al4Si8O24]•12H2O
Previously called "Herschelite" until it was renamed in the late 1990's. Forming glassy spherical crytal aggregates to 3mm across on white Phillipsite. Overall 2 x 1.5 x 1cm.
Glassy, translucent blue micro crystals to 1.5mm in a cavity of Penroseite matrix. Both have been tested by EDS. There is a good possibility that some of the orange crusts can be cleaned off of the Chalcomentite to further expose the crystals.
Golconda Summit, Humboldt Co., Nevada, United States
Micro crystals of Chalcosiderite to <0.25 mm.
Cooke Collection
Chemical Formula: CuFe+++6(PO4)4(OH)8•4(H2O)
Size: Miniature
Light green curved microcrystals of Chalcosiderite to < 0.25mm and as a fine microcrystalline crust on matrix. Associated with translucent blue spheroids of Apatite, gemmy green prismatic Libethenite, and orange-brown micro Jarosite. Chalcosiderite is a more rare copper phosphate and a member of the Turquoise group.
