I've recently purchased this great high quality well executed piece that seems to be a squared "bowl" (too shallow to call it a vase and too deep to function as an ashtray). It is approximately 95mm (3.75") high and 105mm (4.13") wide. The edges are all nicely beveled and it seems to have 2 glass layers (inner layer is colored and outer is clear). What I assume is the maker's mark seems to be etched and I can make out the large letters to be "EXBO" (the "O" is suspect) and one other letter that I can't make out (or is a part of the letter that I read as an "O"). The bottom of the mark seems to read "CZECHOSLOVAKIA" which I assume is the country of origin. There is no date or number mark, although I do realize that Czechoslovakia separated into the Czech Republic and Slovakia in 1993 so the piece is at least 20 years old. My research has turned up nothing and I'm asking for your assistance. There is one unique feature on the bottom that is a swirl of the design that is repeated as a spiral line around the 4 sides.