Lets be honest, we all have time to run a few experiments which take a while - no one is going away for Easter.
Here is how you can start making crystal Easter eggs at home, and check in on them every day to see how they have grown! By Easter Sunday you should have a few nice crystal Easter eggs to decorate the house.
Growing a crystal involves making a supersaturated solution, and then cooling the solution around a seed crystal (something for the crystals to attach onto), which will grow into a large crystal. A supersaturated solution is an unstable solution - there is more solute (the thing you have dissolved) than the solution can hold when it is cool. As the mixture cools, some of the solute comes out of solution - when you let it cool slowly and without much movement it will form large collections of molecules in a very even shape, a crystal. Salts form cube shaped crystals. As the salt comes out of solution, molecules will deposit themselves in an orderly structure, layer upon layer upon layer and you will end up with lots of cube shaped crystals.
If you put something which is in an egg shape into the solution for the crystals to grow on, you will end up with a sparkly crystal egg, made up of lots of small cubes. We made our eggs with Borax. You could use another salt, or maybe sugar. You'll need to adjust the quantities significantly though. If you give it a go, comment here so others can try it.
To make your crystal Easter eggs you will need (per Easter egg):
- 8 tablespoons of Borax (you can get it in the laundry isle at the supermarket)
- 2 cups hot water
- Food colouring
- Cotton thread
- 1 paddlepop stick or skewer
Step 1: Make your Easter egg foundations for your crystals to grow on out of pipecleaners. Shape the pipecleaners into the egg shape and then tie a piece of cotton thread about 15cm long to the top. Try to make them pretty small...
Step 2: Make your supersaturated solution of Borax. To do this bring 2 cups of water to the boil, take it off the heat and stir in 3-4 tablespoons of Borax per cup of water. If this all dissolves add an extra tablespoon of borax, and stir well. Continue adding borax till no more will dissolve in the hot water. You want the water to be clear, and not cloudy so add the extra borax slowly and stir well inbetween additions. This isn't a step for little kids as it involves hot water and Borax certainly shouldn't be eaten.
Step 3: Put a few drops of food colouring into a jar. Your jar should be big enough to suspend the "egg" so that it doesn't touch the sides or bottom of the jar (see ours below). Once you have tested the length of string required to suspend the egg, tie the thread to the paddlepop stick or skewer you will use to hang it inside the jar.
Step 4: Take the egg out, and dip it into the Borax solution, so that it is totally saturated. Put it aside. Pour the Borax solution into a jar - fill it most of the way up.
Step 5: Suspend your pipeclearer egg into the solution.
Step 6: Cover the top of the jar with anything - cardboard, a plate etc.
Step 7: Watch and wait! As time goes by you will see small crystals starting to form around the egg, and they will grow and grow till the whole structure is covered.
Step 8: Enjoy your sparkly eggs!
I'll post an update on how our eggs are coming along.