Acid rain is a mixture of material from the atmosphere that contains higher than normal levels of sulfuric and nitric acid. Burning fossil fuels releases nitrogen oxides and sulfur dioxide into the atmosphere, creating acid rain. Many power plants burn fossil fuel and release emissions into the atmosphere. In many cases, prevailing winds can distribute the acid rain produced by one power plant over hundreds of miles.
While acid rain may have an extremely damaging effect on certain materials, other materials may only be slightly damaged or not damaged at all while exposed to acid rain. Acid rain can easily and aggressively eat through certain materials like calcium carbonate. Limestone and marble are easily damaged by acid rain because they contain a large percentage of calcium carbonate. Acid rain can also corrode some metals like iron, severely compromising the integrity of the iron. More durable types of rock and metal like granite and stainless steel can hold up to weathering, corrosion and the effects of acid rain better than other materials like marble and iron.
Most granite can hold up well to regular acid rain exposure. Granite is a very durable type of igneous rock. Igneous rocks are formed when magma cools in pockets beneath the Earth's surface. On the Moh's scale, which measures a material's hardness, granite offers a 6.5 in a range from 1 to 10 where lower values indicate softer materials. The large percentage of quartz composing granite makes it one of the hardest available types of stone. Granite is dense, nonporous and can easily resist the damaging effects of acid rain.
Many types of metal are very susceptible to acid rain corrosion. Stainless steel is one type of metal not easily affected by acid rain exposure. Stainless steel is an alloy, a material created by combining metals together to create a completely new material. Stainless steel is comprised of a majority percentage of iron, which can easily be damaged in acid rain. To gain resistance to corrosion, chromium and other materials are added to an iron base, creating stainless steel. Stainless steel can be permanently left in environments where acid rain is regularly present and remain unaffected.