Hello John and Christine,
thanks so much for taking the time to reply! I started ploughing through pages on here after I posted my message and after seeing something about something or other which I now can't remember/work my way back to, I googled whatever the new reference point was and an identical style of objects came up diffferent pieces (cups and jug), but unmistakably the same style and colour. It is on ebay Italia and is attributed to Fratelli Toso o Venini, 1930. I am very wary of identifying anything solely via ebay as people get things wrong or hope for the best, but I'm going to do further searching on vetro nero pasta vitrea rossa (I think it's a glass paste made to look like ceramic which my very limited searching has told me was made by about 3 Venitian producers at the time.) BUT..now you've told me about the Czech connection, I'm going off searching in that direction too. I've just taken not-too-great pics of the mark underneath a glass and will post as soon as I can get them up, thankyou so much once again, very much appreciated,
Fiona.