China, 200-300 BC., Qin dynasty and earlier, anonymous, Ban Liang, Hartill 7.6.

China, traditionally attributed to Qin dynasty, anonymous, ca. 200-300 BC.,
Æ cash / Ban Liang (ø 34,5-35 mm / 11,18 g), cast bronze, 10 x 10 mm square – eight pointed center hole, irregular edge,
Obv.: 半 - 两 , “ban liang“ in archaic script from right to left flanking center hole, no rims.
Rev.: plain and flat, no rims (square eight pointed center hole).
Hartill 7.6 ; FD 385 ; Schjöth 79-82 .

A chinese ounce (liang) weighs about 16 grams. The earliest "Ban Liangs" weighed around 5 to 20 grams, with the weight flactuating over this wide range. Emperor Shi Huangdi introduced monetary reforms, fixing the weight around 8 grams - The "History of Han" says:
When Qin united the world, it made ...[the currency] of bronze, which was similar to the coins of Zhou but bore an inscription Ban Liang (''''Half Ounce") and was equal in weight to its inscription.

Qin Shi Huangdi (259 BC 210 BC), personal name Ying Zheng, was king of the Chinese State of Qin from 246 BC to 221 BC during the Warring States Period. He became the first emperor of a unified China in 221 BC. He ruled until his death in 210 BC at the age of 50. Qin Shi Huang is a pivotal figure in Chinese history. After unifying China, he and his chief advisor Li Si passed a series of major economic and political reforms. He undertook gigantic projects, including the first version of the Great Wall of China, the now famous city-sized mausoleum guarded by a life-sized Terracotta Army, and a massive national road system, all at the expense of numerous lives.