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
Gemstone Publishing Gemstone Publishing Gemstone Publishing is an American company that publishes comic book price guides. The company was formed by Diamond Comic Distributors President and Chief Executive Officer Steve Geppi in 1994 when he bought Overstreet. Gemstone published licensed Disney comic books from June 2003 until November 2008. The company has also reprinted EC Comics of the 1950s. BOOM! Kids acquired all comic publishing licenses regarding Disney characters in the second half of 2009. Gemstone's flagship publications were comic books featuring Disney characters; particularly the Donald Duck/Uncle Scrooge comics of such Duck artists as Carl Barks and Don Rosa, and the