A little known mining area exists on Chunky Gal Mountain, near Franklin, Clay County, North Carolina. This area produces fine crystals of corundum that often occur in a matrix of smaragdite, a green-colored chromian actinolite. Some of the corundum from this location shows a classic trivalent chromium-activated red fluorescent response under long wave UV. This series of photographs shows several specimens of corundum, var. ruby, as individual hexagonal crystals, and in smaragdite matrix, collected in 2017 from Chunky Gal Mountain.
Brightly fluorescent hexagonal ruby crystals collected from Chunky Gal Mountain, North Carolina, seen under long wave UV (365nm).
Same two ruby crystals shown under visible light. The largest crystal, at left, is approximately 23 mm across.
Specimen containing numerous red fluorescent ruby crystals in smaragdite matrix, collected from Chunky Gal Mountain, North Carolina, seen under long wave UV (365nm). The bright blue/white fluorescing mineral appears to be aragonite, and is phosphorescent (see next photo below).
Following exposure to long wave UV, the aragonite shows green phosphorescence.
Same specimen as above, shown under visible light. The size of this specimen is approximately 98 x 55 mm.
A second specimen containing numerous red fluorescent ruby crystals in smaragdite matrix, collected from Chunky Gal Mountain, North Carolina, seen under long wave UV (365nm). As in the specimen above, the bright blue/white fluorescing mineral appears to be aragonite.
Same specimen as in photo above, with the aragonite showing green phosphorescence following exposure to long wave UV.
Same specimen as seen in the above two images, shown under visible light. Note the numerous grains of green-colored smaragdite. The size of this specimen is approximately 98 x 35 mm.