Bornite

Massive bornite with minor chalcopyrite on altered, franklinite-willemite-calcite ore from Franklin. The bornite shows the iridescent, blue to violet tarnish characteristic of the species. Most of the willemite in the ore is brown and appears serpentinized, but nevertheless retains its bright yellowish-green fluorescence SW. Near the bornite mass, in contrast, the willemite is bleached and nonfluorescent. Along one end of this specimen is a small and inconspicuous mass (5-6 mm across) of an unidentified mineral in dark brown, fibrous crystals embedded in the bornite. This may be aegirine; see the mention in Dunn (1995, p. 431). If so, the specimen is probably from the same find as BRN7. Incidentally, a typewritten note by Frank Edwards claims this mass of bornite was the “largest raised.”  While perhaps true at one time, larger masses are now known to exist.
This specimen can be traced back to the collection of Billy Ball, a NJ Zinc Company employee who for years worked on the picking table at Franklin. The Ball collection was later dispersed by Schortmann's Minerals (Easthampton, Massachusetts). From there it entered the collection of Frank Edwards (longtime editor of The Picking Table) and eventually became part of the Lee Areson collection. In 1989 the Areson collection was purchased by Richard Hauck, from whom Earl R. Verbeek purchased this specimen, gave it catalog number ERV-501, and in May 2022 donated it to the Franklin Mineral Museum, where it remains as their specimen FMM-2742.

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