Common bleak extracted from the scales of the common bleak, so-called "Essence Orientale" or "pearl essence", (used in making artificial pearls) which is crystalline guanine. Common bleak The common bleak ("Alburnus alburnus") is a small freshwater coarse fish of the cyprinid family. The body of the bleak is elongated and flat. The head is pointed and the relatively small mouth is turned upwards. The anal fin is long and has 18 to 23 fin rays. The lateral line is complete. The bleak has a shiny silvery colour; and the fins are pointed and colourless. The maximum length is approximately 25 cm. In
David B. Bleak being wounded himself, Bleak rushed the Chinese troops multiple times and killed five of them—four using only his hands—before assisting the wounded, and shielding another soldier from a grenade blast. Bleak is credited with saving the patrol's wounded and ensuring that all of its members returned to allied lines. For these actions, he was awarded the Medal of Honor. In the years preceding and following his military service, Bleak worked numerous jobs around Idaho and Wyoming, working as a rancher, dairy farmer, truck driver, and meat cutter before retiring as a radioactive waste technician at the Idaho National Engineering Laboratory.