Hello and welcome.

It is indeed Chinese, but it is not a Chinese coin. Rather, it is a Chinese charm. Specifically, an "eight trigrams" charm. See
these zeno.ru database pages for many similar examples; yours seems to be a match for
this one; the inscription
zhan xie zhi gui literally translates to "chop-up evil, cure ghosts/demons/spirits".
The "eight trigrams" on the other side are not characters or letters in an alphabet, but Taoist religious symbols.
Wikipedia.
I cannot tell how old it is. They have been making charms like this in China for hundreds of years, but this one does not look old. Probably Taiwanese (or perhaps made in Korea), late 20th century.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis