A carved ivory 'Eighteen Luohan' plaque, Qing Dynasty 19th century, of slightly curved trapezoidal form following the curvature of the tusk, elaborately carved on one side in deep and pierced relief with the eighteen Luohan, some seated, some standing and one riding on a tiger, each carrying musical instruments, banners or flowers, in a rocky landscape with plants and trees and with a dragon emerging from cloud scrolls, the reverse carved in low relief with sages variously occupied in a pavilion garden, wood stand, box (2) 34 cm