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
Varieties of Chinese Varieties of Chinese Chinese, also known as Sinitic, is a branch of the Sino-Tibetan language family consisting of hundreds of local language varieties, many of which are not mutually intelligible. The differences are similar to those within the Romance languages, with variation particularly strong in the more mountainous southeast. These varieties, often called "dialects", have been classified into seven to ten groups, the largest being Mandarin (e.g. Beijing dialect), Wu (e.g. Shanghainese), Min (e.g. Hokkien), and Yue (e.g. Cantonese). Chinese varieties differ most in their phonology, and to a lesser extent in vocabulary and syntax. Southern varieties tend to have