Ancient India as described by Megasthenês and Arrian/Frag. L. B
Fragm. L.B.
Plin. Hist. Nat. IX. 55.
Of Pearls.
Some writers allege that in swarms of oysters, as among bees, individuals distinguished for size and beauty act as leaders. These are of wonderful cunning in preventing themselves being caught, and are eagerly sought for by the divers. Should they be caught, the others are easily enclosed in the nets as they go wandering about. They are then put into earthen pots, where they are buried deep in salt. By this process the flesh is all eaten away, and the hard concretions, which are the pearls, drop down to the bottom.