Marked 925 Mayan Aztec Calendar Coin Bracelet

Marked 925 Sterling. From the research I've been able to do, this is a 9" Mayan Aztec perpetual coin calendar marked sterling, although I have not tested it. It has some slight wear on the back and the inside of the clasp, but otherwise it is in good pre-loved condition. A conversation piece if you know what it is. B37