Glass Message Board
Glass Discussion & Research. NO IDENTIFICATION REQUESTS here please. => Bohemia, Czechoslovakia, Czech Republic, Austria => Topic started by: andynic on February 16, 2007, 04:16:14 PM
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::)HI
Was 1930,s opalescent barolac items ever produced with acid etched signatures as i only have pieces that are unsigned or with moulded signature
andy
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Yes, some opal Barolac items were marked with an acid stamp 'Barolac', often seen in combination with a 'Made in Czecho-Slovakia' mark. I have seen the acid mark on barolac palm tree plates and on some of the floral pattern vases.
Steven
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My "Loss of the Revenge" has an etched BAROLAC on the base rim. I don't have a photo of the sig, but here's the vase.
http://www.geocities.com/wwwcga/Barolac.html
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Just added a photo of one of my palm tree plates. Sorry about the poor quality but the acid stamp 'Barolac' mark can be made out on the footrim.
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-5204
Another, less clear mark is also recorded, see the rose vase here: http://www.pressglas-korrespondenz.de/aktuelles/pdf/pk-2004-2w-geisel-schalen-barolac.pdf It was being offered on ebay some time ago and I identified the vase for the seller. This is the only example of this particular style of mark I have ever seen, however.
Steven
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The one on your Palm tree plate is identical to the one on my vase. Great photo Steven. I described mine as etched, but your "acid stamp" is right on.
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Thank you Glen,
Another interesting observation is that Barolac produced a number of different types of opal glass. One appears to be a heat reactive type, presumably similar to 'pearline' type glass. This is characterised by a strong opalescence towards the rim and is more visible at the surface of the glass. The more opaque areas often have a matt appearance, this appears to be a result of a chemical change within the metal rather than a later treatment such as acid finishing, etc.
The other principal type appears more similar to the opalescent glass produced by Lalique, Jobling, etc., where the opacity results from partial crystalisation within the thicker parts of the glass which cool more slowly. Barolac glass of this type often has a more blue appearance and shows a more concentrated opalescence, visible deep within the glass.
A comparison of the two types may be seen here:
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-4323
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-2438
The only pieces of barolac I have seen with an applied colour/ patina (green on the Loss of the revenge and seahorse vases, purple on the iris vase and pink on the roses vase) have been of the heat reactive type, likewise I have only seen the acid stamp Barolac mark on heat reactive opal pieces (though a number of these pieces also appear unmarked).
The items with the Lalique type opalescence that I have owned or handled have been either unsigned or marked with a moulded signature, with or without an additional acid stamp 'Made in Czecho-Slovakia'. It is only this type of opal that I have seen combined with acid matting/ selective polishing.
The above observations may not be conclusive as they are, due to comparitive rarity of early Barolac, based on a limited number of observations of items from my own collection or those items which I have seen offered for sale. If anybody has any further information on Barolac opalescent glass or has any pieces which contradict the above I would be very interested to hear about them.
Finally, another mark recorded on Barolac is a small, acid stamp 'Tchecoslovaquie' presumably on items produced for the French market. The only examples I have come across with this mark are my mystery opaque black vases, believed to be early production.
Steven
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For what it is worth.....
I can confirm Barolac opalescent glass, satin finished was being produced post-war, at least until 1949, at Rudolfova hut'. The advertised colours were: amber, grey (smoke), blue, pink and opal. No mention of other colours. There is no mention of enamelled or laid-on colours, though there is evidence that patterns such as "Boule" were being produced in opaque colours with enamelled decoration. I wonder if these dark colours and decorated items came much later, with production at Libochovice, as this is the only plant I can find still producing refined pieces, and very late ie 1970s and 80s.
Also, for Glen, no mention of iridised finishing.
Regards,
Marcus
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Marcus,
I've often wondered about the age of these items, it would seem that the different techniques used to create the opalescence and in finishing the items do suggest that they might be from different times, however, I am confident that the pieces with applied colours are earlier than the 1970s, certainly comparing them to the current Libochovice made vases, the quality of moulding and finishing is significantly higher and many show significant signs of age/ wear.
Applied colours must at the very least predate 1981 as The 'Loss of the Revenge' vase illustrated in Cyril Manley's Decorative Victorian Glass has an applied green stain.
There was also a deep blue opal produced and I have seen two examples of the 11100 vase in this colour. See http://www.pressglas-korrespondenz.de/aktuelles/pdf/pk-2006-3w-bateman-barolac-vase-fische.pdf for an interesting example with electroplated silver overlay to rim and foot.
Steven
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Sorry, Steven,
A combination of posting late and bad phrasing, which needs both an apology and clarification.
Clearly, pieces marked with the Tchechoslovaquie impressed mark pre-date 1939. What I should have made clear, is the dark colours were produced pre-war, but do not appear in the immediate post-war list of colours. I know that Inwald used at least two trade-marked opalescent glasses, and probably others. "Duritopal" was used predominantly for utility ware, though that does not preclude its use for decorative items. Another type, which, according to Jackson's "20th Century Factory Glass", was called "Transopal" is likely to have been the metal used in the second of your comparative images.
"There is no mention of enamelled or laid-on colours". Sorry, I did not make it clear that whatever the nature of pre-war production, at the point in time the article was written, there did not appear to be discussion of the above techniques.
If their use returned, I think it would have been much later at Libochovice. However, as you rightly observe, the quality of the moulds was not a patch on the earlier items.
With regard to the silver finishing on your blue vases, might I suggest that the method of application is not electroplating, given the non-conductivity of glass, and hence its use for electrical insulators.
When I worked in the UK ceramics industry, Johnson Matthey made a decorating lacquer or solution, in which precious metals could be suspended, and then be painted onto an item. These were then carefully re-heated, not to a very great temperature, the solvent being driven off, leaving the precious metal bound to the surface. I presume the Czechoslovakian glass and ceramics industry must have had access to something similar.
Regards,
Marcus
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The technique of gilding on glass mentioned with regard to Johnson Matthey involves the use of gold chloride and ether, the ether absorbing the gold from the precious metal salt, forming a brown solution or lustre. The ether evaporates as the lustre is applied, and the item is then heated to aid the shine when polished.
Similar method of production for silvering.
Regards,
Marcus
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Hello Marcus,
Thank you for the clarification and for the explanation of the techniques used for creating metallic finishes. I had considered electroplating though as I understand that in certain processes for silvering glass an initial conducting surface treatment is fired on, then silver is subsequently electroplated onto this conductive surface.
I suspect that the initial treatment would be as you suggest, a lacquer applied and reheated but this could then be used to provide a conductive surface for the electrodeposition. I feel that this has been used in this case as the silver layer is quite thick.
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Hi Steven,
I had not considered the use of preparatory conductive treatment. However the use of a lustre to deposit the initial electro-conductive surface means that, particularly as gold and silver are fine conductors, a thin initial treatment would allow the vase to be used as the cathode, within the electro-plating process, for further enhancement of the depth of decoration.
Regards,
Marcus