Pearl Essence

a mixture of the calcium salt of guanine with a nitrocellulose lacquer, forming a viscous mass with a silvery color, resembling in appearance mother-of-pearl. Pearl essence is used to coat paper, leather, glass beads, and plastics. The raw material used in its preparation is the crystalline substance (calcium salt of guanine) found in the scales of some fish (bleak, sichel, and bream), which is removed from the surface of the scales by stirring them in gasoline (or kerosene) with a blade mixer.