oh yes, see what you mean.
However I think ?? they were the biggest producer of Bohemian glass during that period, so it could be possible they produced it and it was then decorated by an external source/glasshouse/finisher I guess.
So for example, I have a Harrach piece that has been documented at Harrach (they sent me the drawings) and I can see the drawings are the design of my piece (because it is a very unusual shape and design) but without the enamel decoration. I also know the company it was sent to. So either it was drawn without decoration but was still enamelled at Harrach, or it was outsourced to be decorated , or it was decorated when it reached the company who ordered it. If you see what I mean? But in all three instances, still made at Harrach.
My first port of call for yours would be Josephinenhutte or Schachtenbach if it were Bohemian, simply because there should be pieces online available to search to get some ideas. I don't know the names of other possible makers but there probably were other possibles as well.
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