Aluminium amalgam with it to form the amalgam. This process can continue well beyond the immediately exposed metal surface, potentially reacting with a large part of the bulk aluminium before it finally ends. The net result is similar to the mercury electrodes often used in electrochemistry, except instead of providing electrons from an electrical supply they are provided by the aluminium which becomes oxidized in the process. The reaction that occurs at the surface of the amalgam may actually be a hydrogenation rather than a reduction. The presence of water in the solution is reportedly necessary; the electron rich amalgam will oxidize
Amalgam tattoo common sites, although any mucosal site in the mouth is possible. It is painless, and appears as a blue-black or grey discolored macule on the surface of the mucosa. The borders of the tattoo are variable, and may be well defined, irregular or diffuse. Amalgam tattoo is caused by implantation of amalgam into the tissues. It may occur in several ways: Over time, the amalgam particles embedded in the soft tissues corrode. Macrophages take up the exogenous particles, and the silver in amalgam leads to staining of collagen fibers. A similar appearance can be caused by implantation of graphite (e.g.