Barium (atomic symbol Ba) is an alkaline Earth metal. Barite (also spelled baryte) is a mineral composed of barium sulfate. It is used in paints, inks, paper, and rubber. It is also used in radiology for diagnostic…

Fluorite (also called fluorspar) is the crystal form of the inorganic compound calcium fluoride. The term "fluorescence," a type of luminescence by a substance that has absorbed light or radiation, is derived from this…