I have a number of Peill & Putzler vases, and so far always managed to find the etch mark, but I can't find one on this vase after checking the bottom and the surface very carefully.
From what I've read in 20th Century Factory Glass, the Peill double P etch mark was used from 1970 onwards, and swirling bubble vases were produced before that time, so perhaps unmarked - that is, if the book is correct on this.
I totally agree that Germany is the place to look - but is there a experience with similar Peill vases to specifically point there? I've tried to find something similar, but I don't think it fits the schleiergraphite range, and I haven't been able to find examples from the swirled bubble vases from Peill.
Astrid