First, we used layers of grated milk and white chocolate and pressed them into a sedimentary rock. We then put them into the fridge and once they had solidified we cut them open to see the rounded grains, just like limestone and sandstone rocks. We then used heat and pressure to change the sedimentary rock into a metamorphic rock by using heat and pressure. When we looked inside, we could see layers, just like the rocks slate and gneiss.