Yesterday, we completed a hardness test using our finger nail and a pin. We scratched the surface of a variety of rocks and discovered that the hardest rock was granite, as this was incredibly difficult to scratch. As a class we agreed that chalk was the softest rock. The children understood that they had to be incredibly careful with the pin. They even identified how make this experiment fair.
The children had to work out the names of each rock by closely examining the rocks and reading their descriptions. The rocks that were identified were the following: marble, granite, chalk, slate and sandstone. They did a fantastic job!