Ancient Chinese carved jade statue KISSING DOVES, 30 cm, Shang Dynasty (1700-1027 BC). Moh's scale of mineral hardness: 5.5 (Normal range for nephrite jade is 5.0-6.5); Length: 30 cm = 12 inches; Weight: 1,100 g = 2 lb. 7 oz. Condition: age related weathering of jade; Age: Shang Dynasty; References: Jade has been used in virtually all periods of Chinese history and generally accords with the style of decorative art characteristic of each period. Thus, the earliest jades, of the Neolithic Period, are often quite simple and unornamented ritual and impractical versions of the tools and weapons that were in ordinary use, often much larger than normal examples. These are presumed to have been symbols of political power or possibly religious authority. The bi and cong are types of objects only found in jade in early periods, and probably had religious or cosmic significance. The bi is a circular disk with a hole, originally usually plain, but increasingly decorated, and the cong is a vessel, square on the outside but circular inside. In later literature the cong represents the earth and the bi the sky. Jades of the Shang (18th–12th century BC), Zhou (1111–255 BC), and Han (206 BC–AD 220) dynasties are increasingly embellished with animal and other decorative motifs characteristic of those times, and craftsmen developed great skill in detailed small relief work in objects such as the belt-hooks that became part of elite costume. In later periods ancient jade shapes, shapes derived from bronze sacrificial vessels, and motifs of painting were used, essentially to demonstrate the craftsman's extraordinary technical facility. During Neolithic times, the key known sources of nephrite jade in China for utilitarian and ceremonial jade items were the now depleted deposits in the Ningshao area in the Yangtze River Delta (Liangzhu culture 3400–2250 BC) and in an area of the Liaoning province in Inner Mongolia (Hongshan culture 4700–2200 BC). As early as 6000 BC, Dushan Jade has been mined. In the Yin Ruins of Shang Dynasty (1600 BC to 1050 BC) in Anyang, Dushan Jade ornaments was unearthed in the tomb of the Shang kings.