Calcite “Cup Calcite”, “Flower Calcite”   Bao Shan, Yunnan Prov., China.  These strange crystals appeared several years ago, were always uncommon and always expensive.  They are formed much like an overgrown pyromorphite, vanadinite or mimetite crystal being hoopered and hollow.  This one measures 8.4 cm long and is a floater with only one very minor chip (tough to find).  Entirely hollow down middle and could be substituted for a shot glass!  Priced to go.  95$