Remove candle wax from glass container by placing candle in freezer overnight. The wax should pop out when you remove it from the freezer and turn it upside down, but you can use a butter knife to loosen it if needed. (You can also break the glass container and remove the wax by placing the candle it in a plastic grocery bag and smashing it until the glass breaks, but be very careful! After glass has been removed, rinse off the candle to get rid of any shards.) Cut the wax into thick chunks.
Cut the top off an old milk carton and thoroughly clean and dry it. Then glue the wick to the bottom of the carton with waterproof glue. Wrap the top of the wick around a pencil or chopstick and set it on top of the carton.
Melt the wax using a double broiler. When it's ready to pour, fill the milk carton with ice chips. Then pour the melted wax into the carton and cover the ice.
Let the candle sit for a couple of hours and pour out the water from the melted ice. Then tear away the carton from the candle. Depending on how the ice melted in the milk carton, you might have some pieces missing from the candle. This adds character! Trim the wick, light your candle and enjoy.
Use medium-sized to large-sized ice chips and not ice cubes to make these candles, as large cubes can cause your candles to fall apart. Also, try not to use too many small pieces of ice or your candle might fall apart in the middle.