Garnet minerals

   Garnet is a group of minerals, some of which are used as gemstones. They are common in several igneous and metamorphic rocks. Many elements are included in the different varieties of garnet, such as calcium, magnesium, iron, aluminum, chromium, manganese, and titanium. Garnets often occur as crystals, some several inches in diameter. Colors vary from yellow to red, green, purple, and brown. Large quantities of the minerals are found in Bohemia, Ceylon, and South Africa and in the United States in Pennsylvania, New York, Virginia, California, Alaska, and many other states.