For those interested in labels, I found a nice source for the Czech labels around 1991:
A few months ago I bought a secondhand booklet called 'Bohemia Crystal, Glass that conquered the world' by Antonin Langhamer and Ladislav Pekar. It was published in 1991 by Glassexport Ltd on the occasion of the Universal Czechoslovak Exhibition in Prague 1991. Not much of a read, but at the back, page 46 and 47 it shows a lot of trademarks and labels, including which ones were used at that time (in 1991 presumably).
Every factory has it's own symbol (and it conveniently lists the correct factory with each symbol). I counted 13 different symbols, excluding the special labels like Exbor, Moser and Skrdlovice. The symbol labels are ovals with Bohemia in big letters, Czechoslovakia in small print below that, the symbol of the factory and an indication of hand-made or cut crystal or not.
Kaliglass: yellow labels with black letters. If it's handmade, it says so on the label. If it doesn't say anything, it's machine made.
Lead crystal: blue label with gold letters. If it's handcut, it says 'hand cut lead crystal over 24% pbo' on the bottom of the label. If it's machine cut, it says 'fine cut lead crystal over 24% pbo'. If the label is red and it just says 'lead crystal over 24% pbo' at the bottom, it's pressed crystal.
From the text I think that this particular system of distinguishing labels was in use since 1989.
It says on the same page that the terms Bohemia Crystal and Bohemia Glass were trademarked since the second half of the fifties, but no explanation was given when they used 'glass' or when 'crystal' with the generic glassexport labels.