This is what I did with my family this week: We made large marbles
out of ice.
Marvelous giant marbles
We took a few good quality balloons,
put 3 drops of food coloring into them and then we filled them with
water. We placed each into a round bowl and let them freeze outside.
The forecast shows temperatures below -10'C for the whole week. A perfect
time for making giant marbles out of ice. To start with we prepared 2 water
filled balloons and let them freeze outside over night.
Filling a balloon with food coloring and water
Frozen over night
Why do we put the balloons into a round bowl? If you place a water
filled balloon on a flat surface and let it freeze then you will get
something that is round except for the bottom side. The bottom will
be flat. You can avoid that by placing the balloon in a round bowl.
This will result in an almost perfectly round marble.
Placing the water filled balloon in a round bowl while freezing will result in a round marble.
Removing the balloon
Removing the balloon
A few words of warning:
Use good quality balloons. You don't want them to pop and dye everything around. Look for "Latex Helium Grade" balloons.
Food color is non toxic but it can stain porous materials permanently (e.g the cement between the tiles in your bath room).
The ice marbles will melt at one point. Food color stains porous
stone and it will take several months until the sun has bleached the color.
Don't place the marbles on a unistone driveway. Put them in an area with
grass under the snow.
