Dims: 3.2 x 2.4 x 1.9" (8.1 s 6.1 x 4.8 cm)
Wt: 10.1 oz. (286.3 g)
Sussex County, New Jersey, U.S.A.
This hand specimen consists of scores or even hundreds of tiny Franklinite crystals that are embedded in a calcite matrix. These Franklinites do not exceed 0.2" (5 mm) in diameter, and most are smaller than that. Most of the visible crystals are broken and incomplete, but a few areas of fresh breakage on the calcite contain many intact ones. They tend to have rather warped, cube-based forms, and a few show definable octahedral or even dodecahedral forms. They are all black and have a dull, submetallic luster. They are accompanied by many equally small, brown willemite crystals that are also embedded in the calcite. It is easiest to pinpoint these when the specimen is bathed in shortwave ultraviolet light (see the second image), as the calcite glows a moderate red, and the willemite glows bright green. Being fluorescently inert, the Franklinites do not glow.