Transition refers to the raw edge of the silver as well as silver’s classification as a transition metal (in the d block of the periodic table of elements). Mirrors are made by UV bonding stones to a clear piece of glass. The decorative stones also act as the anchoring points for the steel mounting brackets attached behind. To create the mirror surface, a silver nitrate solution is poured onto the glass and chemically bonds to the surface. Not enough silver is poured on purpose to create a fade to clear.
A coat of black paint is applied behind, at the center of the mirror to give it more reflectivity and a clear coat of lacquer is applied around the transitional edges. This protects the silver from oxidizing. The beautiful transitional edge is actually an incorrect use of the product and does not create as strong of a bond to the glass and is more susceptible to removal from the glass surface and should be treated with extreme care.