Ex Bob Trimingham; quoting from his collection catalog card (which accompanies the specimen): " A freeform mass of black tennantite with two doubly terminated crystals [to 1.3 cm] in one corner &faces elsewhere, with a sprinkling of fine black scattered microcrystals (15x) of pseudohex[agonal] chalcocite. Micro potential. Fine crystals...Fine gray digenite...at red arrow area." White, nondescript gypsum also present. Chalcocite - Cu₂S and digenite - Cu₉S₅ are end members of a solution series and may not be easy to differentiate visually on some specimens.