Abstract: During the Qing Dynasty (1644-1911), court artisans carved agates with a high degree of technical ability and inventiveness. Agate wares produced during the reign of the Yongzheng (1723-1735) and Qianlong (1736-1795) emperors exploit the full breadth of chromatic effects and degrees of translucency offered by these silicate stones. During this period, agate carvings were produced in high numbers, and imperial commissions made conscious use of the stone's unique material qualities. Because the geological environment in which agates are formed affects their pigmentation, the range of agate colors recorded in historical documents and seen in surviving objects reflects a variety of geographical origins. This paper considers how agates were understood by scholars and appreciated by emperors at a time of territorial expansion and interest in new minerals.