This cobalt blue cut-to-clear crystal glassware set is a style popular in the mid-20th century. This type of glassware involves overlaying a layer of colored glass (in this case, cobalt blue) over a clear crystal base, then cutting away portions of the colored layer to reveal the clear crystal underneath, creating intricate designs.

The set is most likely Nachtmann, a well-known German manufacturer of fine crystal glassware, and their 'Traube' (grape) pattern is a classic design often found on decanters and glasses. The combination of the rich cobalt blue color and the detailed grape vine motif suggests a piece intended for serving wine or other spirits in an elegant setting. Sets like these were often used for special occasions and were considered a mark of sophistication.

****One of the glasses has been repaired and the glue has yellowed.