Rough piece of orange/brown sphalerite var schalenblende intermixed with white dolomite. The schalenblende fluoresces a nice orange, while the dolomite fluoresces white. The fluorescence is best observed under longwave UV light (or even 405nm blue laser). The dolomite is slightly phosphorescent. There are also patches of a metallic mineral, likely galena.
Specimens with two or more bright colors under longwave are highly sought pieces; most LW minerals are only a single bright color - #LWMulticolor
From: Raibl Mines, Cave del Predil, Tarvisio, Udine Province, Friuli Venezia Giulia, Italy
Dimension: 8 x 5 x 5 cm, 265 g