On Shuffle.us, Gold Coins (GC) don't have any real cash value and cannot be cashed in for prizes.
Gold Coins are awarded as a daily login bonus or included with certain purchase bundles.
They are intended solely for fun and cannot be exchanged for prizes or converted into Shuffle Cash.
Playing with Gold Coins does contribute to your VIP progress, although at a slower rate than Shuffle Cash.
Every 2,000,000 GC played contributes 1 XP!