Optisch

While the word "optisch" (i.e. optical or visual) is not actually a decor, it is an important feature of many Loetz decors.   Various "optisch" designs were specifically designated in the Loetz production notes. These "optisch" designs were given unique and descriptive names such as "bandoptisch (ribbon)", "quadratoptisch (square)", "gewaltzt (rolled), "schiefgewalzt" (wrong-rolled), etc.  Molds were then made to impress the specific pattern into the glass.  This feature was used mostly in clear and translucent colored glass or to enhance simple decors such as Ausf 97, Luna, Melusin, Metalin, Syrius, Vulcan, etc. For example: "Quadratoptisch" = Square pattern impressed in the glass vs "Carrirt Optisch" = a Checkered pattern.