"Rocks, minerals and soils have different characteristics that set them apart from others. Find out about the properties of rocks such as slate, marble, chalk, granite and pumice. Which rocks split? Can you find a rock that floats? Test permeability. Can liquids pass through?" - Science Kids
splits- slate and chalk
permeable- chalk, pumice
doesn't wear well- chalk
Do the test on all sorts of rocks and classify them into each category.