Why do Chinese coins have a hole in the middle?

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Tags

1. #square
2. #first
3. #would
4. #represents
5. #could
6. #universe
7. #easier
8. #strung
9. #scraping
10. #holes
11. #place
12. #center
13. #carrying
14. #coins
15. #reason
16. #china
17. #round