Pearl is the pearl formed in such bivalve as Pteria martensii (Dunker) (Fam. Peteriidae), Hyriopsis cumingii (Lea) or Cristaria plicata (Leach) (Fam. Unionidae) , etc., when it is irritated by foreign substance.

Action: To calm the nerves, to eliminate corneal opacity, to counteract toxicity and promote the growth of new tissue.

Indications: Palpitation and insomnia; convulsion, epilepsy; nebula; skin ulcerations difficult to heal.

Usage: Mostly used in making pills or powders; appropriate quantity for external use .

.