Those are the auction price in China for the 2017 Latest auction of China rare Circulating coins. NOT be so happy there you might have some at your home. It might be the bullion version which not worth the same price. One grade lower also can lead to significant lower price Bullion coin might be in multi million in circulation. Proof might be less than 10-50K. Specimen coin are rare. I am not circulating coin collector BUT I trade some with friends who know much better than me. My Knowldege on china circulating coin is limited. If you keen buy Mr Sun book. however it is in mandarin. 3 coins at USD22K USD 19K USD16K for a copper coin PF66/67 get USD45K when the overall pop of the coin get low grade and rare the price will remain good regardless of grade. Therefore, you need to analysis the situation rather than just chasing the grade result most of the time without proper analysis of situation.