The version of the triskelion with a face inside is indeed symbolic of Sicily.
Your "coin", however, is not a coin. It's a souvenir medal depicting the ruins of the Greek colony of
Tauromenion, on Sicily. I suspect it was made in recent times, specifically for using on tourist souvenir pieces like your bottle opener. The same scene of the "Greek Theatre" depicted on the medal is shown on the Wikipedia page.
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