An unusual Sino-Tibetan silver inlaid casket and cover, Wanli six-character embossed mark and of the period, of rectangular shape, flanked with two upturned 'crane' handles, the long sides each decorated with a circular 'prunus' panel, and other auspicious motifs on a fretwork silver ground, the cover pierced and applied with roundels and sword-shaped motifs and scrolling dragons around the rim, all covered with silver-work 'lei'-patterns, raising to a 'shou' knob, 34 cm x 16 cm x 29 cm, Note: This type of metal work was produced in exceedingly high quality and vast number in Tibet as early as the 14th and 15th century. Iron is one of the five treasures of Tibetan Buddhism, amongst gold, silver, copper and brass. Hence it is not surprising that the Tibetans made so many pieces of lowly iron and lavishly decorated them with gold and silver. The unique technology has been known as 'damascening' to Europeans, but called 'Derge' in China, the name of the town through which the metalwork was brought to the China-proper. Different from the common inlaid-works, 'Derge' works have their surface of the wrought iron abraded and then gold and/or silver beaten on in the pattern of decoration desired. Known pieces with Chinese reign-marks usually bear the Yongle, Xuande, and Qianlong marks. Qianlong emperor, especially, commissioned a group of Tibetans to produce vessels and objects of daily use, such as brush pots and plates, besides those for the traditional ceremonial and religious purpose. Compare a globular jar and cover also from the Wanli period, illustrated by Rose Kerr in Later Chinese Bronzes, London, 1990, p. 55, no. 44, from the Victoria and Albert Museum ref no 108-1876. The revitted ornaments resemble those on this lot. Kerr further suggests such metalwork was produced by armourers due to the rivetting technique used in its assembly