St. Petersburg Mining Museum’s researchers have recreated the look of rare 19th-century fluorite vases. …Matthew Boulton, an English manufacturer, was one of the first in Europe to start making decorative items from fluorite, a rare naturally occurring mineral. In late-18th-century Birmingham, his factory produced such art objects as candelabra, bowls, potpourri vases. They were not made by hand, though. The workers carved them using machines powered by a steam engine.