Gold from the Warring States to the Eastern Han Dynasty usually refers to real gold. It should be noted that gold at that time was mostly horseshoe-shaped or cake-shaped, each piece was "one catty". At present, the weight of gold cake and horseshoe gold in the picture is generally about 250 grams, which is the weight of one catty in Han Dynasty. One or two at that time was not one or two now. One catty is sixteen taels, and one tael is actually about 15.625 grams. For the casting of gold cakes, one piece just needs almost one catty, that is, one gold.
After the Eastern Han Dynasty, gold was not widely used in society, so we look at the records after the Eastern Han Dynasty. If the reward is gold, it will generally tell you clearly that there must be a unit. But the "money" in the "100,000 yuan" is what we often call copper coins, thanks to the government's vigorous promotion. Then let's look at "rice is expensive, 1 million dollars" and "jewelry is worth 700 thousand dollars". A penny equals a penny, which means a copper coin.
In the Ming and Qing dynasties, if only "gold" was said, it was silver. This mainly appears in the notes of literati, saying that whatever is worth is worth as much gold as silver. For example, it is recorded in "Qing Chao Po" that dignitaries are willing to spend money and buying snuff bottles has become a fashion. "Broken leaves are the end, mixed with flower dew, and a device is worth dozens of gold. It is a gift for the nobility. " Dozens of gold here refers to dozens of taels of silver, not dozens of taels of gold. It can't be copper coins. I bought it for dozens of coppers, and you are embarrassed to give it as a heavy gift.
To sum up, it is a serious mistake to say that ancient "gold" refers to copper. Gold in the Spring and Autumn Period is about copper. Gold in the Warring States, Qin and Han Dynasties is usually called gold. After the Han Dynasty, the gold added with the unit of measurement "two" must be gold, but we said that "there is a reward of 300,000 yuan" and the reward is Kong Fang copper coins. There was no unit of gold in the Ming and Qing Dynasties, such as "worth tens of gold", where one gold refers to one or two pieces of silver. From the late Qing Dynasty to the Republic of China, "one gold" was a silver dollar.