The most popular sizes of gold bars in China before liberation were mainly "large yellow croaker" and "small yellow croaker".

"Big yellow croaker" refers to twelve gold bars. According to the old system, 1 catty is 16 taels, and 1 tael = 500/16 = 31.25 grams. Therefore, the equivalent weight of the "big yellow croaker" gold bar today is 312.5 grams.

Originally, "large yellow croaker" was a common size, and wealthy families usually saved a few gold bars as a minimum deposit. But later, gold was expensive and silver was cheap (the legal currency of the Republic of China was silver-based, and the earliest legal currency of one yuan was priced according to one silver dollar). Ordinary people also wanted to buy gold, and the "big yellow croaker" was obviously too expensive to afford. So the gold shop cast one tael of small gold bars (equivalent to 31.25 grams today), commonly known as "little yellow croaker".