Thank you all very much!!
Astrid, I did consider German, but I was not sure which company would fit to such a bottom finish -- thanks for your hints! Will have a closer look into those...
Ivo, Skruf was what I thought when I picked it up -- but the one similar piece I have handled so far was signed and had a totally flat base...
But that may not be the rule?
Dirk, Cathy, that sounds like a reasonable explanation for the ground out pontil mark; would turn mould-blown be the right expression for that?
(BTW, I have a Ruda glasbruk vase with a ground out pontil, which I believe to be mould-blown as well)
I had a short look through the Gralglas CD yesterday, but didn't see anything similar. Would the bottom finish be congruent with other Gralglas pieces?
What I might add is that there has been put quite some effort in this piece -- I have not seen such a high-gloss polished base yet...
And the glass looks so "clear" -- can it be lead crystal?
Michael