Calcite {CaCO3}: Fl. red-orange SW
The Noble Pit at Sterling Hill has outcrops of calc-silicate rock containing meionite (one of the scapolite minerals). This often fluoresces a very subdued magenta-red in short-wave ultraviolet. It is beautiful once your eyes have adjusted to the darkness of the room.
The non-fluorescent mineral in the specimen above is a clinopyroxene such as augite or diopside.
It's tough to get larger specimens from the outcrop, since the rock is so hard to break. Calc-silicate rock is tough. A 20-lb sledge seems so big and burly until you try using it on an outcrop of the stuff. Then you might as well be using a 2-ounce tack hammer.
There are some loose pieces of meionite on the floor of the pit, however; these have weathered to chalky white on the exterior. Some of this still fluoresces fairly well. When it's been outside too long, though, it develops a brown "rind".
Fluorescent meionite (with the possible exception of the Canadian variety known as "wernerite") does not display well next to willemite or scheelite; I keep meionite and other dimly-fluorescing minerals down toward one end of my display shelves. The best way to light this stuff is to have a D-68 or a Triplebright about 6 inches away from it.
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