Hold the daguerreotype in your hand and gently tilt it back and forth. The mirrored image will appear positive and then negative as the light hitting the image changes. Color pigment was often applied. Early cases were made of wood and leather. Union cases, made of thermal plastic, date from the 1850s.
Common plate sizes: Whole plate............6 ½" x 8"½" Half plate...............4¼" x 5½"	Quarter plates.........3 ¼" x 4 ¼" Sixth plate..............2 ¾" x 3 ¼"