"It appears so simple to explain that it is no longer amongst the mysteries of the world. But in actual fact, much remains unknown about the pearl. We barely understand how it is formed. And it has been discovered that all shells can produce them. As a consequence, a whole range of them may be found, reflecting the immense variety of molluscs and shells: blue ones, red ones, white, green, black, yellow, orange and even speckled ones." (Hubert Bari) The fascination of this book is the way it effortlessly combines scientific, historical, cultural, and practical information.