Metallic ores contain metals, such as copper, aluminum, gold, silver, and iron. Non-metallic ores are ores such as sulfur, limestone, and quartz. Fossil fuels were made through heat, pressure, and time acting together on the remains of ancient plant and animal life. Oil or petroleum was formed from the remains of microscopic marine organisms and is found in shale or sandstone. Coal is made from the remains of plants and animals originally found in ancient swamps.
Natural gas is found on the top of the pools of oil.
The process of making any fossil fuel took millions of years to complete. However, the use of fossil fuels can occur during a two hundred year period. Plants and animals are considered renewable resources because they can be replaced in a relatively short time. Animals are an important source of food and fiber for clothing. This standard exposes students to the varied impacts that people have made on the natural environment and the resources contained within this environment.