This Cup, Saucer, and Plate all have the same beaded pattern. A celery tray was in the L. E. Smith factory "morgue" in wistaria (amethyst), which would date the pattern to circa 1936. Tom Felt stated that "since Smith made tons of glass in black, it certainly seems reasonable that the set in the gallery is the same pattern." The wistaria tray is shown on p. 76 in the first edition of his book L.E. Smith Glass Company The First Hundred Years.
