Sodium amalgam sodium metal in mercury or the reverse. Sodium amalgams can be purchased from chemical supply houses. Since its introduction in the 1880s by students of Robert Bunsen, Julius Tafel and Hans Goldschmidt, sodium amalgam has also been used in organic chemistry as a powerful reducing agent, which is safer to handle than sodium itself. An example of its use is in the Emde degradation. A sodium amalgam is used in the design of the high pressure sodium lamp providing sodium to produce the proper color, and mercury to tailor the electrical characteristics of the lamp. Sodium amalgam is a by-product
Dental amalgam controversy condoned the use of dental amalgam. In 1855, Dr. J. Foster Flagg, a professor of dental pathology in Philadelphia, experimented with new mixtures of amalgam. In 1861, he presented his findings to the Pennsylvania Association of Dental Surgeons and, in 1881, he published his book, Plastic and Plastic Fillings (Figure 4). (Amalgam fillings were often called "plastic fillings" at the time.) The inevitable result of this affair was that silver amalgam was proven to be, "an excellent filling material," and expanded dentistry's, "ability to save teeth." Around the same time, John and Charles Tomes in England conducted research on the