The word in question is gabish, and occurs in Job xxviii. 18. Treating of wisdom, in that magnificent passage beginning, "But where shall Wisdom be found, and where is the place of understanding?" the sacred writer uses these words, "No mention shall be made of coral, or of pearls: for the price of wisdom is above rubies."
In consequence of the labour and research required for seeking wisdom, it was proverbially likened to a Pearl, and in this sense we must understand the warning of our Lord, not to cast Pearls before swine. The "pearl of great price" is another form of the same metaphor.
The substance of Pearls is essentially the same as that which lines many shells, and is known as "mother of pearl."
Although a large number of shell-fish secrete "mother of pearl," only a few of them yield true Pearls. The finest are obtained from the so-called Pearl oyster, an illustration of which is given on the preceding page.
The Ancients obtained their Pearls chiefly from India and the Persian Gulf, where to this day the industry of Pearl-fishing is still carried on by the natives.
The oysters containing the Pearls are brought up from the bottom of the sea by divers, who go out in boats to the fishing-grounds, which are some distance from the shore.
Leaping naked into the water, carrying a heavy stone to enable him to sink quickly to the bottom, the diver descends to where the oysters lie, and secures as many of them as possible during the limited time that his breath lasts. On an average the divers remain under water from fifty to eighty seconds, though some can endure a much longer period.
Sharks are the special dread of Pearl-divers, and many are carried off by this fierce monster of the deep. To arm himself against their attack the diver carries a sharp knife, and instances are known of his having attacked and fairly defeated the dread destroyer in its own element.