Ornate brass shell frame 4.25x5.5" has glass over an engraved brass mat and holds translucent white glass sheet bearing artist-rendered Lincoln portrait that approaches photographic likeness in its detail. Tiny ink name along image's bottom edge appears to read "W. Penny Artist." Known as a lithopane, light transmits through the glass. Left and right of the portrait are details of pale bluish-gray clouds. Issued c. 1890s as a commemorative item. Superb workmanship. A few tiny tarnish dots on brass matte, all else is Exc.