Both colors were used by a wide variety of companies.
I'm inclined to go with Ivo's Oiva Toikka attribution pro tem, otherwise iittala.
Adam & others
Beautiful Sklo Union Paperweight in neodymium with bubbles perfectly balanced & as good as any piece of Caithness. 3.6” high and almost bullet shaped it has a yellow Sklo label.
To note and clarify:
As mentionned in other topics Marcus has noted that the Bohemia label was used on the products of factories NOT part of Sklo Union as well.
Neither ZBS nor Chribska were part of Sklo Union.
(PS don't feel bad ....I'm only one step ahead of you on this complex subject)