Aluminium and iron are both metals. They are both found in ores. They must be extracted from these before they can be used.Brick is made from clay while glass is made from sand. Both these materials are found in the Earth's crust.Common rock that are used commonly for construction:Marble,Granite and LimestoneThe ''scratch'' test will determine which is hardest. The hardest rock will scratch the softest the most.Sedimentary Rock-Laid as layers of sediment in the ocean. Compacted by layers on top.Igneous Rock-Formed when magma cools slowly undergroundMetamorphic Rock- High pressure and temperatureLimestone is sedimentary so it is the softest out of the three. Marble is metamorphic, it is harder than the limestone. Granite is the hardest as it is igneous.Thermal decomposition of Limestone: Limestone → Calcium Oxide (quicklime) + Carbon dioxideThermal decomposition is a reaction in which, when heated, one substance is chemically changed into at least two substances.