In February 2007, I purchased a plate which I recognised as being from a range, made at the Rosice factory of Sklo Union, and designed by Jírí Brabec, around 1980.

The "wood-grain" plate was of  particular interest as it is iridised. As this is not a common treatment for Sklo Union items, I contacted Glen Thistlewood, the highly respected English authority on iridised and Carnival glass, to ask if this was a treatment  she recognised. The iridising is applied to the base of the plate, the upper surface being un-treated. Being no expert on iridising techniques and technology, I had no idea, whether this iridising had been applied whilst the plate was still hot, or indeed, whether it was possible to iridise just one surface.

Glen immediately had her suspicions, that this was not a stannous salts iridising, (hot treatment) based on the pre-dominantly blue and green colour, and suggested that what we are looking at here is  post-production iridising, using a process know as "low-vacuum iridising". The pertinent questions were: Is there any loss of the iridised coating? If so, is there a base-coat which shows through? If so, what is that colour?



As the image above shows, there is loss of the iridised coating, and the base-coat is a pink-silver metallic colour. With these answers, Glen was able to suggest that this plate was probably iridised by a German company LGW, Lleinauer Glaswaren, (see Glen's article here: http://www.geocities.com/carni_glass_uk_2000/LGW.html ) who appear to have specialied in "low-vacuum" iridising, from the 1940s until the late 1980s, and who are known to have purchased blanks from several major European glass manufacturers. It has been difficult to trace particular items back to the specific manufacturers, but in this case, we clearly have a Brabec 5214/270 plate for Rosice. It is also the case that I have seen other, clearly identifiable Sklo Union items showing this treatment, including a Rudolf Jurnikl (Rudolfova hut') ash-tray, from the early 1960s, iridised in a similar manner.