Sphalerite and calcite from Franklin
A vein of fluorescent sphalerite (mixture of bluish, orange, and violet) cuts through the center of bright calcite (orange). This came from a rock we dug up at the Buckwheat Dump. It wasn't on the surface.

This variety of sphalerite sometimes fluoresces brightly under midrange UV (302 nanometers).  It is also quite fluorescent and phosphorescent under longwave, but then the calcite doesn't usually respond.

Notice that the calcite's fluorescence immediately dulls to violet as it gets closer to the sphalerite vein.  Something in the sphalerite has "quenched" the calcite's fluorescence.  Perhaps it's an excess of manganese?  Iron?  It's hard to say without doing some tests.

Specimen is about 4 inches wide.

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