WANGDA SHOWCASES WON THE TENDER OF MUSEUM DISPLAY CASES PROJECT FOR RU KLINS PORCELAIN MUSEUM which has much strict and critical standards for anti-bandit safety,air-tightness,anti-explosion performance and also conservational lighting system within museum display cases. Like Ding ware, Ru ware was produced in North China for imperial use.The Ru kilns were near the Northern Song capital at Kaifeng. In similar fashion toLongquan celadons, Ru pieces have small amounts of iron oxide in their glaze thatoxidize and turn greenish when fired in a reducing atmosphere. Ru wares range in colour from nearly white to a deep robin's egg and often are covered with reddish-brown crackles. The crackles, or "crazing", are caused when the glaze cools and contracts faster than the body, thus having to stretch and ultimately to split. The art historian James Watt comments that the Song dynasty was the first period that viewed crazing as a merit rather than a defect. Moreover, as time went on, the bodies got thinner and thinner, while glazes got thicker, until by the end of the Southern Song the 'green-glaze' was thicker than the body, making it extremely 'fleshy' rather than 'bony,' to use the traditional analogy (see section on Guan ware, below). Too, the glaze tends to drip and pool slightly, leaving it thinner at the top, where the clay peeps through. Ru Ware Bowl Stand, detail of crazing; V&A FE.1-1970 As with Ding ware, the Song imperial court lost access to the Ru kilns after it fled Kaifeng when the Jurchen-led Jin dynasty conquered northern China, and settled atLin'an (present-day Hangzhou) in the south. There, the Emperor Gaozong founded theGuan yao ('official kilns') right outside the new capital in order to produce imitations of Ru ware.However, posterity has remembered Ru ware as something unmatched by later attempts; Master Gao says, "Compared with Guan yao, the above were of finer substance and more brilliant luster."