Pale green, fibrous actinolite and violet fluorite with white calcite from a fault or fissure zone in fine-grained, well-foliated, feldspar-pyroxene gneiss. The actinolite has been freed from the enclosing white calcite with acid, but some of the calcite remains and is visible in the photo. Its bright red fluorescence suggests derivation of the specimen from within or near the Sterling Hill orebody. Now specimen FMM-9115 of the Franklin Mineral Museum, it was collected in the early 1990s by Bob Jenkins during his extensive mineralogical studies underground at Sterling Hill.
Identifier: ACT17a Locality: Sterling mine, Ogdensburg Specimen size: 11 x 7 x 5 cm Photo credit: Earl R. Verbeek