Gemstone few as one in a million atoms. These so-called impurities are sufficient to absorb certain colors and leave the other colors unaffected. For example, beryl, which is colorless in its pure mineral form, becomes emerald with chromium impurities. If manganese is added instead of chromium, beryl becomes pink morganite. With iron, it becomes aquamarine. Some gemstone treatments make use of the fact that these impurities can be "manipulated", thus changing the color of the gem. Gemstones are often treated to enhance the color or clarity of the stone. Depending on the type and extent of treatment, they can affect the
USS Aquamarine (PYc-7) for disposal. She was sold to Colonel E. M. Grimm of Columbus, Ohio, in 1947, and her name changed back to "Seawolf". She was sold in 1954 to Ennolls A. Stephens of Irvington, Virginia, owner of The Tides Inn, Irvington, and renamed "Miss Ann". In 2008, "Miss Ann" was sold to private interests who placed her in Charter Service on the Potomac River. In 2014, she is located at the Colonial Beach Yacht Club in Colonial Beach, Virginia. USS Aquamarine (PYc-7) USS "Aquamarine" (PYc-7) was a patrol boat in the United States Navy during World War II. Later known as