I had questions about historical coin values.
I ended up reading https://coininvest.com.ua/chervonets-skilky-tse-naspravdi-povna-istoriya-vaga-zolota-nominal-i-suchasna-tsina/.
It was hard to find well-structured information. Most sources were too general.
The breakdown of gold weight and value was very helpful.
On this page I found structured info.
Good expert content if you’re interested in coins, gold, or real asset value.