Pearl. A shelly concretion, usually rounded, having a brilliant luster, with varying tints, formed in the mantle, or between the mantle and shell, of certain bivalve mollusks (especially in the pearl oysters and river mussels) and sometimes in certain univalves. Its substance is the same as nacre, or mother-of-pearl. Pearls which are round, or nearly round, and of fine luster, are highly prized as jewels. The are sold by carat grains, instead of carats.
“Are you dejected? here is comfort. Are you sinful? here is righteousness. Are you led away with present enjoyments? here you have honours, and pleasures, and all in Christ Jesus. You have a right to common pleasures that others have, and besides them you have interest in others that are everlasting, that shall never fail; so that there is nothing that is dejecting and abasing in man, but there is comfort for it in Christ Jesus.”
–Richard Sibbes, Description of Christ