: to make (something) more attractive usually by putting something on it.
There are several types of mercury. They include metallic mercury, and both inorganic and organic mercury compounds. Many of these forms are found in our environment, however, the most common natural forms include metallic mercury, mercury sulfide, mercuric chloride, and methylmercury (http://www.atsdr.cdc.gov/toxprofiles/tp46.html).
Methylmercury is a type of mercury, a metal that is liquid at room temperature. A nickname for mercury is quicksilver. Most compounds containing mercury are poisonous. Methylmercury is a very poisonous form of mercury. It forms when bacteria react with mercury in water, soil, or plants. It has been used to preserve grain that is fed to animals. Methylmercury poisoning has occurred in people who have eaten meat from animals that ate grain that was treated with this from of mercury.