Limited US edition, number 559 of 675 copies. L�onard Rosenthal was a famed Parisian jeweller who personally commissioned Dulac's illustrations; they first appeared in a French edition in 1920. As noted by Dulac's bibliographer, "[Dulac's] plates, truly genius, do much to bring a fanciful touch to the otherwise stark exposition of a treatise on pearls. There is whimsy, too, in the personalities imparted to the various species of marine life that are worked into the designs. Dulac had always enjoyed ornamenting the total book in which his plates appeared, producing end papers, title page designs, covers, etc. But here he outdid himself." Hughey 54e. Large quarto. Original quarter cloth and grey boards, spine lettered and with pictorial decoration in gilt, front cover with pictorial decoration and printed label, patterned endpapers, top edge gilt, others untrimmed. Frontispiece and nine colour plates with printed tissue-guards. Corners and lower extremities worn, occasional light foxing; a very good copy.