neutrons. The number of electrons and protons are always equal, so there are 13 electrons in each atom of aluminum.
             Small quantities of aluminum are found throughout the universe. In fact, around 2,000 atoms in every billion in the universe are aluminum. Most of the aluminum found on Earth probably formed at least five billion years ago in the heart of a red giant star. Inside this star, the nuclei of many helium atoms were fused together by the enormous pressures and temperatures to make heavier elements such as aluminum. The world we live in formed from the remains of such a giant star. As the hot young Earth slowly cooled, heavy elements such as iron, sank to the core. Aluminum was so light it floated up to the surface to form the solid crust, along with the elements silicon and oxygen.
             Since it is the most common metal in the world, it follows that most minerals, rocks, and soils are rich in compounds containing aluminum. Igneous rocks develop from molten rock, either volcanic lava on Earth's surface or magna deep underground. Granites and dolerites are examples of igneous rocks. These rocks a
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