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
Bowhead whale Bowhead whale The bowhead whale ("Balaena mysticetus") is a species of the family Balaenidae, in parvorder Mysticeti, and genus "Balaena", which once included the right whale. A stocky dark-coloured whale without a dorsal fin, it can grow in length. This thick-bodied species can weigh from . They live entirely in fertile Arctic and sub-Arctic waters, unlike other whales that migrate to low latitude waters to feed or reproduce. The bowhead was also known as the Greenland right whale or Arctic whale. American whalemen called them the steeple-top, polar whale, or Russia or Russian whale. The bowhead has the largest mouth