Today we conducted an experiment to test how hard different types of rocks are and we looked at them using a hand lens. We used the nail, penny, and tile test to see what type of scratch it made. The color it leaves will tell you how hard or soft the rock is. We tested nine different types of rocks in all. Tomorrow we will take a look to analyze the information to see which category the rocks would fall under: metamorphic, igneous, or sedimentary.