Found this on the internet - looks alot like the coin you are posting! https://www.liveauctioneers.com/item/8308298_1853-half-dollar-california-gold-coin-gc1156
Who knows but if it is the same coin it sure has made it's way around - the auction I posted was from Dec 2010
Certainly not the same , remarkable coincidence though. Original posters coin shows the 'D' in 'Gold'.....Other photo does not.