Ive had one of these for years, i was just thinking about selling it, when i spotted its twin on ebay,
"unusual shape multicolour bowl" so i bought it,(cheap

) and now have a pair.
I have written on a scrap of paper, Kralik, similar example , see Le genie Verrier de L'europe , by Guiseppe Cappa.
Does anyone have the book? I remember seeing another on a website somewhere, which i presume
mentioned the above.
Cheers
Andy