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Author Topic: Small facet cut stem ruby glass - Gorge de pigeon / Gold-ruby instead  (Read 11288 times)

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Offline flying free

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I'm just adding these photos as they might be of interest to someone at a later date.

The rim of the little likor glass is very fine and only 1/16 " at it's absolute widest (2mm?)(i.e. where the cutting forms a point or angle).  I cannot see that it might be cased.  Nothing shows on the photos or to the eye.

The rim of the red becher next to it is more than twice as wide in diameter.  You might be able to see on the photo where the casing is done and then cut through.  The clear layer can be seen inside.  It is cased only on the outside as there is a clear picture engraved on the front and the base is clear.
The facet cut panels are cut into the red overlayer but don't go through to the clear so it was a fairly good layer of red.

The foot picture is just to show how streaky the red actually looks when held up against a white sheet.  It doesn't look streaky in real life or held up to normal daylight - just looks a pretty red colour.  It is clean so all those bubbles and bits are in the glass as well as the streaks.

The stem is cut quite deeply as on previous pics so don't think that was cased either.

None of this probably helps on id but just thought it might be interesting for others to see.

It weighs not a lot.  I haven't scales light enough to weigh it properly.

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Offline flying free

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Whilst I understand Ivo’s comment in reply #51 regarding my discussion comments about gorge de pigeon glass:
I will email you when I get back to my research notes. Until then, I think that ruby the colour is not to be confused with goldruby the process. It is not just dealers and curators who use the term loosely, it is also people who should know better like cmog. And let's not obfuscate the matter with other glass types which may or may not be related. This may be a multiple and complicated misunderstanding. Any testing method for gold content would be a destructive one.

A reply in #36 was presented in a very conclusive way regarding the references by the Hermitage to their ‘gorge de pigeon’ pieces being gold ruby glass:
Reply #36 Oldglassman said:
'Of course you are quite correct but again I would contest the use of the word "evidence", the  items linked to above are clearly wrongly attributed by the Hermitage , and could be very old information , personally I would then question the validity of the other entries

and I actually feel it is an interesting discussion on whether or not ‘gorge de pigeon’ glass is wrongly identified as gold ruby glass by the Hermitage, since this is on a thread where it has been stated that gold ruby production ceased in the 1740s and then was not produced again until it’s rediscovery c.1835 by Pohl
(and since I have produced other references  in reply #30, #38, #49, to gold ruby glass being produced before 1835)

I understand obviously, that all the authors in those references I have given could be wrong, if, as Ivo says, it is not possible to identify gold ruby glass without destructive testing methods. However, should we also consider that it may be that they (there are a number of references now, not just the Hermitage) have concrete evidences, which have enabled them to state that those pieces are gold ruby glass.

In addition to the two references I gave directly regarding ‘gorge de pigeon’ glass ( on reply#46 point 2) - La Cristallerie de Clichy Roland Dufrenne, Jean Maës, Christian Capdet, Bernard Maës; and Musee des Arts Decoratif) and the third less specifically but still related reference on that same reply (Walter Spiegl),  I have now obtained the book referenced by Bonhams to whom Oldglassman linked as evidence on the reply #36:
‘Baguiers et Verres A Boire du XIXeme siecle’ - Leon Darnis dated 2014

Under a paragraph on ‘gorge de pigeon’ glass it says the following (google translate has been used, please see the original text which I have added at the bottom of this post, for the French description in the book):

Quote – ‘Regarding the gold salts ,, they are used in the form of 'Purple of Cassius' (which we later called 'precipitate of Cassius'), so called in reference to the Dutch XVII century that invented this preparation. This is a mixture of stannous chloride with a solution of gold in aqua regia (nitric acid and hydrochloric acid). Tin was often used in excess and, when cooked, it led to the emergence of a purplish color called 'Pink Hydrangea' or more commonly 'pigeon throat'. This is the usually accepted on this coloration release. But one could believe that there is another possibility. The glassmakers were wont to use manganese as dioxide, called 'soap glassmakers' because it was like bleach vis-a-vis the impurities. However, the excess manganese gave a tint 'Cerulean roughly Dew', that is to say, purplish, with the colorless crystal. In the same way, the manganese in excess or not, could give a purplish hue in the presence of purple of Cassius. Taking advantage of these reflections, it seems that the opaline 'pigeon's breast' that have milky parts probably part of an associated excess tin perhaps to the presence of manganese. However, opaline 'pigeon throat' of a well purplish red color might stand out more from the presence of manganese.’

I may be wrong, but it appears to me that they used gold in the form of pourpre de Cassius to make their Gorge de Pigeon glass.  From what I have read, that appears to be the way the gold is used in the gold ruby glass?

Again I may be wrong, but it appears to me the difference between the 'appearance to the eye' of the colours of the glass (gold ruby (red) v gold ruby (gorge de pigeon)) is explained by the occasional excessive use of tin ('Tin was often used in excess and, when cooked, it led to the emergence of a purplish color called 'Pink Hydrangea' or more commonly 'pigeon throat'.') in the production of the gorge de pigeon and the effect that had in the making when combined with the manganese, thereby producing the bright pinky-purply gorge de pigeon.

So it seems to me reading all the references, that both use the gold in the pourpre de Cassius.

I think this is a reasonable explanation as I said before, as to why the Hermitage have their gorge de pigeon coloured glass listed as gold ruby. 
It might go some way to explaining why 'gorge de pigeon' ( French glass) and  'Lilac agatin glass' (Bohemian -Buquoy ) and  the other 'Purply-pink-opaline-glass-that-looks-like-gorge-de-pigeon' glass (Russian (?) glass in the Hermitage museum that is not gorge-de pigeon incorrectly identified) is so rare.

M. Darnis has 6 pieces of the gorge de pigeon glass in the book dated at 1820-1830. 

I have now provided many references (not just 'opinions') to say why I disagreed with this statement:
'‘Reply #28
 Once again from Corning ,   first phase came with Kunckel c 1684 and ended probably along with the death of his patron in 1688, the second phase began c 1719 and continued in a lesser scale till the 1740s , nothing then till rediscovery c 1835 by Pohl’ – Source given as ‘Glass of the Alchemists’'


If all those references (dating post-2008 when The Glass of Alchemists was dated) are correct then that time frame does not stand anymore. 
If however every single one of those references is found to be wrong, then it's probably a good thing we are discussing it.

m



Original script for reference:
‘Concernant le sels d'or,, ils sont utilisés sous la forme du 'pourpre de Cassius' (que l'on appela plus tard 'precipite de Cassius'), ainsi dénommé en référence au hollandais que XVIIeme siecle, inventa cette préparation.  Il s'agit d'un mélange de chlorure d'étain avec une solution d'or dans de l'eau regale (acide azotique et acide chlorhydrique). L'étain fut souvent utilisé en exces et, à la cuisson, cela entraina l'apparition d'une couleur violacée appelee 'rose hortensia' ou plus couramment 'gorge de pigeon'. C'est là la version habituellement admise concernant cette coloration. On peut cependant penser qu'il existe une autre possibilité. Le verriers avaient coutume d'utiliser du manganese sous forme de bioxyde, appelé 'savon des verriers' car il agissait comme décolorant vis-a-vis des impurités. Or, l'exces de manganese donnait une teinte 'azurée plus ou moins rosée', c'est-a-dire violacée, avec le cristal incolore.  De la meme facon, le manganese, en excés ou non, a pu donner une teinte violacee en presence de pourpre de Cassius.  A la faveur de ces réflexions, il semble que les opalines 'gorge de pigeon' que présentent des parties laiteuses participent surement d'un excés d'étain associé peut-etre à la présence de manganese. En revanche, les opalines 'gorge de pigeon' d'une coloration bien rouge violacé pourraient ressortir davantage de la présence de manganese.’

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Offline flying free

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see above and
The bowl referenced in the first link below is in the book as 'Attributed Bercy' as it says in the Bonhams link provided.
I could not see the perfume bottle in the book.  Is there a reference for this being 'gorge de pigeon'?

Quote:
'http://www.hermitagemuseum.org/wps/portal/hermitage/digital-collection/08.+Applied+Arts/990314/?lng=en
and ,   http://www.hermitagemuseum.org/wps/portal/hermitage/digital-collection/08.+Applied+Arts/802804/?lng=en
both clearly described as Gold Ruby Glass , in fact they are  " gorge de pigeon "  French glass

https://www.bonhams.com/auctions/23557/lot/137/'

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Offline Ivo

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Getting more confusing with every addition. I'm not at all convinced this makes chemical sense. First of all, gold salts do not enter the equasion as the gold in aqua regis is colloidal. Opaline is a strict formula which does not use gold. And Gorge de pigeon actually contains Sn and/or As as an opacifyer - but is not related to opaline, and neither is it gold ruby per se... The notion that glassmakers just threw anything which happened to lie around in the mix is just weird.  It is possible that Sn or Mg or As made it to the Gorge-de-p recipe along with some Au in an acid bath - but why? Except for the Au, these are powders which can be tipped unceremoniously into the batch.

We're just sitting on a huge pile of misunderstandings it seems.  We need the g-de-p original recipe.
Will resume end of this week.

Anyroads, looking through google images I see a lot of opaline and very little gorge. Anything cranberry with some opacity is filed under the prestigious pigeon name.  Just like French dealers will refer to pressglass as pate-de-verre or opaline de foire...

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Offline flying free

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 are you saying that every single reference I have given is incorrect including one which was published a year ago and quoted by Bonhams for their sale of their £6000- £8000 'gorge de pigeon' bowl?

I have commented that there are very few gorge de pigeon pieces around.  I'm not sure where you are finding those that are just called gorge de pigeon without being that.  I haven't looked on google for image references.  I've gone by the books or museum glass sites.  There is not a lot around.  What is can clearly be seen as that.

From what I have read gold is necessary to make gold ruby glass and appears to be necessary to make gorge de pigeon. And I can understand that.  Who mentioned opaline? 'Opaline is a strict formula which does not use gold.'   and ? Opaline is a strict formula?  I thought there were many different ways of making opaline glass - or at least there is more than one opacifier.)

And I am pretty convinced that all the Stevens and Williams alabaster range pieces I own are opaline glass (made from 1914 into the 1930s) and the owner of the company said in his book that the Rose alabaster was made with gold ruby.

I think if the information I provide is going to be refuted then it needs to be with references to demonstrate where I have not understood it correctly.
I am not just willy nilly plucking references or comments out of the air without any thought.

I agree having a recipe for gorge de pigeon would be good. 


m

m

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Offline Ivo

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Will send you the section on opalines as well - AFTER I get back.

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Offline flying free

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I apologise Ivo

... Opaline is a strict formula which does not use gold. And Gorge de pigeon actually contains Sn and/or As as an opacifyer - but is not related to opaline, and neither is it gold ruby per se... .


   Who mentioned opaline? 'Opaline is a strict formula which does not use gold.'   and ? Opaline is a strict formula?  I thought there were many different ways of making opaline glass - or at least there is more than one opacifier.)

m

Clearly I did :
quote
'It might go some way to explaining why 'gorge de pigeon' ( French glass) and  'Lilac agatin glass' (Bohemian -Buquoy ) and  the other 'Purply-pink-opaline-glass-that-looks-like-gorge-de-pigeon' glass (Russian (?) glass in the Hermitage museum that is not gorge-de pigeon incorrectly identified) is so rare.'

That underlined opaline should have read 'translucent' glass, since I do not know if gorge de pigeon or Agatin or what might be the Russian (?) glass that looks like gorge de pigeon in the Hermitage Museum, is opaline or not.

I have seen it discussed under the group 'opalines' for example in this article.  There is a stunning hanging lamp on there (click to enlarge) that was for sale for Eur.18,000 in 2007:
http://www.gazette-drouot.com/static/magazine_ventes_aux_encheres/cotes_et_tendances/opaline.html

I'm sorry.


m



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Offline flying free

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Interestingly the museum has this gorge de pigeon as it's showcase piece on the page titled  L'Opalines

http://www.lesartsdecoratifs.fr/francais/musees/musee-des-arts-decoratifs/collections/dossiers-thematiques/zoom-sur/zooms-sur/l-opaline-5544



'At the end of the eighteenth century, the French manage to imitate the English crystal, renowned for its brilliance. Under the Empire, the color of this crystal gives rise to what we call opaline and what was then called crystal opal or crystal opal color. Realized objects - cups, ring assemblies, vases, chimney linings - first adopting the simple forms of return to antiquity. These luxury items are often given a gilt bronze mount.

From the reign of Charles X, forms thicken, to stretch and conform more beautiful under the Second Empire. The soft colors are followed by more violent tones, inspired by the Bohemian glasses. The delicate shades of pink are obtained with gold salts.

In 1840, for reasons of economy, pink glass is not dyed but lined with colored glass. In the early nineteenth century, Le Creusot, Baccarat and St. Louis are the main production centers. Subsequently, many glassworks are created around Paris: Bercy, Choisy-le-Roi, Belleville Clichy ...'

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Offline Ivo

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Gorge de pigeon is a translucent colour, however it was made. It is French for cranberry and relies on a very small dispersed quantity of colloidal gold in the mix.
Opaline (vrai opaline) is an opaque  crystal formula which can come in any number of pastel colours - including pink, green, white, bleu and others. Will look up the formula later - i have it somewhere.

"Coloured in the mass"  usually means coloured with chemicals which change the base colour. Gold is dispersed, it does not become part of the glass but remains suspended and changes the refraction.  Other red dyes like copper and selenium colour the mass.

Have you noticed how everyone is steering away from this discussion on advanced colour chemistry? It is horribly complicated and before we know it we get quagmired in other peoples misunderstandings. Even big names like Olivié, Mergl and Ricke get their information from other writings and somewhere, along the way, the technical bit disappears under the table. After all, "if it is over my head it must be over everybody else's and people are not interested anyway".
Thank god someone does not take shortcuts here. 😊

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