Same view as in photo GYP4a, here shown under SW ultraviolet light. The gypsum is infused with tiny grains of willemite that collectively cause it to fluoresce green. Alteration of the calcite clasts at right has reduced their red fluorescence in most places. Note the thin rim of brightly fluorescing willemite along the gypsum-calcite contact.
Identifier: GYP4b Locality: Sterling mine, Ogdensburg, NJ Specimen size: 13 x 10 x 4 cm Photo credit: Earl R. Verbeek
