Just adding this before I lose it. Exciting find. I bought a vase many years ago at a fair and just put it away thinking I'd never find out who made it. I think it's the same 'range' as this one but different colourway:
https://antikes-glas.de/en/fritz-heckert/nouveau-vase-from-opal-glass-with-crumbling-fusions-fheckert-othamm-p-1565.html?language=enThe vase in the link is 18cm. Mine is 30cm tall by 12cm diameter base and 7.5cm diameter rim.
Anyone else think they're probably the same maker?
The info and reference on the linked vase at Antiques Neuwirth is : Fritz Heckert Petersdorf, Design Otto Thamm, c1903 (source Lit .: S. Zelasko, Fritz Heckert 1866-1923, Page 201. )
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