Medieval Europe offers a pageant of almost incredible richness: King Arthur and his round table, demons and cathedrals, Charlemagne and his paladins. The Carolingian culture of the late eighth to late tenth centuries (in what is now France, Belgium, Germany, the Netherlands, Switzerland, and northern Italy) offers more than its fair share of achievements. This heavily illustrated study examines one revealing legacy of Charlemagne's heirs and his people--the Carolingian gems of rock crystal, jet, and agate engraved with complex figural scenes, which have never before been studied as a group. These objects have been largely ignored in the scholarship of medieval art, partly because of the difficulty of access. Genevra Kornbluth assembles for the first time all twenty surviving gems, from small seal matrices to the forty-one-figure "Susanna crystal" in London, along with information about lost works. The unique features of each gem are made visible in over 200 detailed black-and-white photographs, often highly magnified and produced using new techniques developed to record transparent engraving. Kornbluth fully analyzes the techniques of manufacture, style, chronology, iconography, and patronage of each gem and examines their social functions, the organization and status of the artisans who created them, and relations between media. The gems are presented as evidence of the rich diversity of the Carolingian culture, rather than as reflections of an artistic program dictated by the imperial courts; they are also seen to be essentially new creations, drawing on earlier visual traditions but adapting their sources to address contemporary concerns.