A design or decoration in a specific pattern, usually simply executed ornaments and flower motifs, either painted with gold in relief or etched with etching ink or chemicals and produced from the late 1880's to about 1912. A decoration number was assigned for each pattern and painted in gold or etched on the bottom of the glass. Decoration numbers were first comprised of two parts consisting of Roman numerals above a slash or bar and then Arabic numerals below the bar (e.g. I/3, I/117, I/123, III/321) and later just a number.
Decorations produced with an inner casing of colored opal glass and a strongly iridescent coating of Silberiris were most likely produced only for a short period from 1902 to 1905.