During its lifetime the pottery absorbs radiation from its environment and it is this which creates thermoluminescence.
The older the pottery, the more radiation it has absorbed and the brighter the pottery sample glows.
By this time, bronze decor had come under the influence of textile patterns and technique, particularly embroidery, as well as of lacquer decor, suggesting the bronze medium’s decline from primacy.
Bronzes decorated in this manner have been found chiefly in the Huai River valley. Perhaps the oldest class is a small clappered bell called ling (鈴), but the best known is certainly the zhong (鐘), a suspended, clapperless bell.
Typical vessels of this phase have been found in a cemetery of the small feudal state of Guo (虢) in Henan province.
The style of bronzes found at Liyu (李峪) in Shanxi (c.
They are graded in size (from about 20 to 150 cm [8 to 60 inches] in height) and tone (covering five octaves), and each is capable of producing two unrelated tones according to where it is struck.
Gold-inlaid inscriptions on each bell present valuable information regarding early musical terms and performance, while a 65th bell with flat bottom called bo (镈) is dedicated by inscription from the king of Chu to Marquis Yi of Zeng (Zeng Hou Yi, 曾侯乙), the deceased, and bears a date equivalent to 433 BC.
Powder samples (from pottery and bronze cores) are mixed with acetone and allowed to settle, so that fine grains, approximately 1/100mm. These grains are deposited and dried onto aluminium discs (for fine-grain analysis) or rhodium (for pre-dose analysis).
Any remaining powder is dried and used for radioactivity measurements to complete the dating calculation. When the glue is dry, they are cut into slices 1/4mm thick with a fine diamond blade. Each slice is soaked in acetone after cutting to remove the glue. The remaining core is crushed and used for radioactive analysis to complete the dating calculation.
Ancient Chinese mirrors were generally bronze disks polished on the face and decorated on the back, with a central loop handle or pierced boss to hold a tassel.