In certain instances, it may be desirable to protect a Daguerreotype from corrosion by the application of a surface coating. Protective coatings must be both chemically and physically non-reactive with the Daguerreotype image material, and, more importantly, must not interfere with the optical properties of Daguerreotypes. Sputtered coatings such as silicon dioxide, boron nitrid, lanthanum hexaboride, aluminum nitride, and titanium dioxide, as well as a vapor-deposited polymeric coating, Parylene C, have been tested. The results of these tests are discussed.