These two blue examples are almost certainly not Chribska according to Jindrich, who very briefly emailed me today, he suggests a number of other Czech factories may be responsible. The problem of certain identification is probably due to paucity of documentary evidence for much pre-1960 Czech glass.
Given how regularly a few of this style of vase bowl etc turn up (at a glance similar to the black Chribska one), I am surprised that not one I have seen or heard about has had a label to point in the direction of origin, other than a general feeling of decent quality Czech pre-1960 production (as confirmed by Jindrich). Any comments are very welcome from others who are interested in these items.
bOBA