What_Are_Rocks_Made_Of

=What are Rocks Made of? =

 We found this information in a video called "Rocks and Minerals."
 * Rocks are made out of minerals.
 * Minerals are made in the Earth.
 * Some minerals are very rare. They are called gemstones.
 * Some jewelry is made from expensive gemstones.
 * Salt is a very common mineral.
 * Pennies are made from copper, a mineral.
 * Some rocks only contain one mineral. Most rocks contain 2 or more minerals.
 * For example, granite is made from feldspar and quartz.