Tags: Chemical Substance, Mineral.
Hardystonite is a rare calcium zinc silicate mineral first described from the Franklin New Jersey USA zinc deposits. It often contains lead which was detrimental to the zinc smelting process so it was not a useful ore mineral. Like many of the famous Franklin minerals hardystonite responds to short wave ultraviolet (254 nm wavelength) light emitting a fluorescence from dark purple to bright violet blue.
