It's not the first such item to me posted on the forum -
here's another one just like it - and we've never had an authoritative or satisfactory explanation for them. There's a link to a Treasurenet thread in the thread I've just posted, but they don't seem to be sure of what it is either.
For all the other similar tokens posted here, the other side has been a blank crosshatching pattern.
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