The large diamond is the wild symbol, it will substitute for all of the other symbols, except for the scatter symbol, to help and form winning combinations.
The scatter symbol is a four-leaf clover and it is key to one of the bonus features.
If you land just two scatter symbols on the reels you trigger the Stamp Spins feature. You start with eight free spins and during each spin between 1 and 5 reels will be randomly stamped. Stamped reels will pay each symbol on the reel in each position. In other words, they do not have to be along a payline on successive reels to award a payout. If a wild symbol lands on a stamped reel then the entire reel becomes wild. If a scatter is on a stamped reel, it pays once only for the reel. Best of all, you can retrigger the feature once to award you eight more free spins during which all wins will be subject to a x2 multiplier.
Minted Money offers a huge top payout of 160 times the total bet if you land five gold coins along a payline. The silver coin can payout up to 80 times the total bet and the bronze coin up to 40 times the total bet. All four of the playing card symbols can payout up to 8 times the total bet.