The inkstone 18th century, the jade plaque Ming Dynasty The inkstone carved in the form of a roof tile with a slightly-flattened centre for grinding the ink, and a quatrefoil well at the top, the stone of dark green tone, the zitan stand and cover similarly arched, the cover inlaid with a pale green jade plaque depicting a stylised chilong, fitted box. 10.5cm (4 1/8in) long. (4).