What you’ll need:
- A jar
- About half a cup of salt
- A spoon for stirring
- 2 toothpicks
- Fill the jar with water.
- Add about half a cup of salt to the water.
- Mix the solution together with a spoon.
- Cut a piece of string with scissors and tie each end to a toothpick.
- Place the string over the top of the jar so that the string dangles into the middle of the solution and the toothpicks hang over the edge.
- Don’t forget to clean up when you’ve finished.
Leave the experiment and wait for salt crystals to form along the string. They are an excellent example of cubic crystals and you can do further research with them by examining them under a microscope.
When you look at various crystals under a microscope you can examine the differences between them: Are they perfectly formed? What shape are they? What colour? Can you see any microorganisms on the crystals?
Crystals can be found grouped together as lots of small crystals or as huge individual crystals. They vary in size from those at the microscopic level all they way up to crystals that are meters in length!
Try collecting a range of crystals for your project, label the different types and make a rock collection box to keep them in.