Combine rum and lime juice in a punch bowl and refrigerate until ready to serve. When you are ready to serve, add orange peel ice block and top with sparkling wine. Pour into a champagne flute and garnish with a mint sprig.
Orange Peel Ice Block Recipe: Fill a small Tupperware container with water and put in the freezer until the top of the water begins to freeze over (approximately 20 minutes). When the top is thinly frozen, cut lengthy twists of orange peel and add them to the water by cracking the top of the ice on one side. Put back into the freezer until frozen solid.