So do you buy $231.30 (custom amount) Coles GC in store or $250 Coles GC and then buy another Coles Gift MC, leaving you with a balance of $18.70 in the Coles GC?Scratch that. Inception definitely possible. A bit of extra work required though. Use your coles gift Mastercard to buy a coles gift card. Then use that gift card to buy another coles gift Mastercard.