Rock and Gem Day / Eggshell Crystal Geodes
Eggshell Crystal Geodes
Older children grow sparkling crystals inside cleaned eggshell halves using an educator-made solution, then watch them develop over a few days.
How to run it
- Wash and dry eggshell halves, removing the inner membrane.
- Have an educator dissolve alum or Epsom salt in hot water until no more dissolves.
- Once cooled to warm, pour the solution over the shells in cups.
- Leave undisturbed for two to four days, then lift out and observe.
You will need
- eggshell halves
- alum or Epsom salt
- warm water
- cups
- food colouring
- gloves
Make it easier or harderYounger children can watch and record, while older children compare salt types and crystal sizes.
SafetyEducators handle hot water and powders, children wear gloves and wash hands, and check for egg allergies.
My Time Our Place · Outcome 4Children observe change over time and practise scientific prediction and observation.
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