In an add-a-? ? ? series (The Book of Diamonds, 1965) this is a firmly packed history of what was the preferred jewel of royalty, the symbol of prestige and power, once much more prominently displayed whether in parures or stomachers. The author traces the pearl's influence (medicinal and magical in very early civilizations), its provenance around the world and in the Americas, and tells stories of the famous pearls (there was a Hope pearl as well as a Hope diamond). She examines their general devaluation and rise of the cultured pearl industry. Luster used to be the determinant of value; today, along with everything else, it's bigness. . . . If you found the earlier book useful, this will certainly be your oyster for along with the substantial information, there are 100 illustrations.