I saw ice lanterns at http://wintercraft.com & thought I could make these without having to buy their expensive kit.
Step 1: Items Needed
-flat rock can be helpful
Step 2: Fill Balloon With Water
I blew the balloon up first to stretch it. Then I filled it like a water balloon. Try to have as little air in the balloon as possible when you tie the knot. This will help your ice lantern to be as round at the top as possible.
Step 3: Freezer Time!
This is where the cup comes in. You want to put the balloon with the knot down in the cup, then put them in the freezer & wait. The time will vary depending on your freezer, size of your balloon, & how full you've made the balloon.
After about 4 hours, I took the balloon out & poked the bottom of it so that the bottom would not freeze over. Then put it back in the freezer. Poke the bottom of the balloon again about every 2 hours.
Step 4: Time to Remove the Balloon
Be sure you're holding the balloon over the sink, cuz as soon as you stick the pin in the balloon, it's gonna be GONE. The water doesn't just trickle out (like *I* thought it might).
Step 5: Ice Lantern Complete!
You now have a cave of ice! Use the flat rock under one side of the ice lantern so that your candle can still get oxygen. These don't melt as fast as you might think, but DO check the water levels fairly often. These would be gorgeous decorations to put in the snow, but are lovely for anywhere that is a little dark. The impurities in the water create really pretty patterns too!
I was shocked how beautiful this turned out the first time I did it! Have fun!
If you make one, post a pic & I'll give you a patch. :)