Eight magnificent micro synthetic emerald cyrstals of 1 to 2 mm are mounted on a round white apparently plastic disk that’s affixed to a round cork pedestal. The pedestal extends from the bottom of a vintage cardboard micromount display case as was favored in the first half of the 20th Century. This mount is from the collection of the late Robert Jacoby. His label notes that it (or perhaps just the synthetic emeralds) came from one F. J. Sperisen in San Francisco.
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