Gold bricks produced by the imperial kiln in Suzhou in eastern Jiangsu Province are not actually made of gold. The smooth, shiny bricks are big and square. They got their name from their quality, the tedious manufacturing process and the high cost involved. The bricks, which have long been used to build imperial palaces, are a specialty of Lumu, a small village near Yangcheng Lake in Suzhou. In the early 15th century when the Forbidden City began to be constructed, the bricks made in Lumu were recommended to the Ming government (1368-1644). Central government officials assigned to Lumu found the yellow earth in Lumu was especially good to make bricks. Besides the special material, the advanced firing technique and the strict firing procedures of the Lumu kiln also contributed to producing the high-quality gold bricks. Thus the Lumu kiln was named the Imperial Kiln by the Ming emperor.