Pectolite (?): fluorescent orange, SW
Margarosanite {Pb(Ca,Mn)2Si3O9} is a rare and classic Franklin mineral that fluoresces blue-white under shortwave UV. It was found, as far as I know, in only two locations: (1) the Parker / Palmer shafts of the Franklin mine in New Jersey, and (2) the Långban mine near Värmland, Sweden. Margarosanite is indeed rare, but its price has become quite high (especially for Franklin specimens). This has made it difficult for the average collector to obtain, except in very small pieces like this one.
A friend tells me the orange-fluorescing material is pectolite. I don't encounter this assemblage often enough to know for sure.
The specimen is only about 1/2 inch across. It is held in a micromount box with a small bit of "Mineral Tack". For fluorescent microminerals, it is nice to keep them in a box which has previously been painted flat black on the inside (photo below shows this in normal light). Notice the margarosanite specimen is just a plain, white rock in daylight. One could easily mistake it for a small chunk of dolomite at first glance.
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