The fantastic conception that pearl formation originates from the dew-drop had been generally accepted from the beginning of the Christian Era until about the 16th century. Androthenus (1550) published his opinion that the pearl is comparable to measly of pigs, and led the way in the scientific investigations of the pearl formation hypothesis. Writers have sum marized these many hypotheses over and over again.
The pearl is a secreted substance formed in the body of certain mollusca, and there are various kinds of pearl which are formed by respectively different causes. Hence, most of the explanations of pearl formation hitherto published do not discuss all but only each particular pearl investigated by the respective author.
We define the pearl as a chemical substance formed in the body of bivalvia, the principal ingredient of which is calcium carbonate containing chonchioline, an albuminoid. We may induce pearl formation by a specific stimulation which in turn causes abnormal multiplication of certain cells which participate in the deposition of pearly substance.
