Hi Poppy, nice ashtray, a very refined and well cut piece, as you would expect from Exbor!
Have you tried a couple of hours browsing the glassreviews on the website of GMB member Jindrich? http://www.cs-sklo.cz/
Is the base acid etched Exbor Czechoslovakia, or Egermann-Exbor CZ Republic? It looks like a 1960's era design, but possibly Egermann-Exbor have reissued it which is why I am asking about the base acid etch.... I do not recognise the piece as by a specific designer unfortunately, but if I see it anywhere I will get back to you. I do not know whether it is possible to contact Egermann Exbor themselves with this kind of enquiry.... I know Moser acid etched pieces are very welcome at the modern Moser site, where the organisation has been extremely helpful where possible to GMB members in the past....