keyword: Pearls – 4 free books.
The Book of the Pearl The history, art, science, and industry of the queen of gems
George Frederick Kunz and Charles Hugh Stevenson
Mineralogy and Geochemistry of Gems
Panagiotis Voudouris et al.
Goods and Services of Marine Bivalves
Aad C. Smaal et al. (editors)
Pearls & Parasites
A. E. (Arthur Everett) Shipley, Sir