The mineral kingdom is the source of base metals, such as copper and iron; "soft stones," such as easy-to-carve soapstone, jadeite, meerschaum and alabaster; hard stones, such as fluorspar and marble; semi-precious stonres such as amethyst, clear and smoky quartz crystal, aventurine quartz, kalgon jasper, Siberian jade, apricot serpentine; and precious metals like silver and gold.
This sample was loaned to the World Chess Hall of Fame from the Saint Louis Science Center Collections.