Extremely rich 8x7x2mm specimen containing abundant inclusions (red arrowed) of brown biraite-(Ce) – an extremely rare silico-carbonate of REE. Biraite contains microscopic inclusions of hydroxylbastnasite-(Ce) and intergrows with its more yellow macro grains well recognisable under magnification (yellow arrowed). Light matrix of the sample represented by pale-greenish, apatite-like strontianite-aragonite with composition (Sr0.5Ca0.5)[CO3] and minor white calcite with typical rhombohedral cleavage. Very valuable addition to biraite in this sample are two complex Ba-Sr-REE carbonates – more brightly coloured cordylite-(Ce) (orange arrowed) and pale cordylite-(La) (pink arrowed). Abundant cordylite gave the name to this carbonatite vein. Another very worthy mineral of this specimen is well formed and complete crystal of black niobochevkinite-(Ce) (with Nb>>Ti) (blue arrowed). This mineral from the locality was recently described in two articles in American Mineralogist. Other minerals represented in the sample are: black ferriallanite-(Ce) (black arrowed), plates of marine green to pearly talc (green arrowed) and reddish-brown thorite (lilac arrowed). Also in the sample, microscopic invisible grains of daqingshanite-(Ce) and -(La), ancylite-(Ce) and -(La), kukharenkoite-(Ce) and carbocernaite. This is a third of minerals known in this remote and hard-accessible locality in a single sample. Note that for two of them (biraite-(Ce) and cordylite-(La)) it is Type Locality. And both them are author’s material. Includes SEM photo with marked place of analyses and EDX spectrum.
Albite Amethyst Analcime Anatase Anglesite Aragonite Azurite Barite Brochantite Calcite Cassiterite Cerussite Chabazite Chalcopyrite Chrysocolla Copper Crocoite Cuprite Dolomite Fluorapatite Fluorite Galena Goethite Gold Gypsum Hematite Hemimorphite Libethenite Magnetite Malachite Mimetite Natrolite Phillipsite Pyrite Pyromorphite Quartz Siderite Silver Smithsonite Smoky Quartz Sphalerite Thomsonite Unidentified Species Wavellite Wulfenite