Topic: Thorn Vases — part 3 — dating and Webb's Alexandrite

[Bernard C]

Here again is a thumbnail picture of the 16" thorn vases I mentioned in part 1 and 2.   Click image to enlarge, or here to SuperSize.



Yesterday I was browsing through the factory pattern books in Reynolds, looking for a Walsh cut glass pattern, when I noticed pattern No. A4066, a group of four fairly conventional thorn vases.    This was a central 10" vase, linked by chains in maypole fashion to three smaller vases and sold "Boxed Complete".    Three pages and a few patterns further on is the date 20.7.27.   So this indicates that Walsh were still making thorn vases in 1927, half a century on from the popular date for them in the reference books, which now must be considered a launch date.

A short time ago I wrote what I hoped would be a helpful reply to Jim Sapp's topic Burmese decorations by Thomas Webb & Sons.   While I was looking at the photograph of the Barbe decorated Burmese ware in Hajdamach, my eye alighted on the little vase at the front of the group on the opposite page, and I realised that I was looking at the graduated colour effect in my thorn vases.   The caption indicates this is an example of Thomas Webb's Alexandrite, which Hajdamach describes "... needed to be reheated twice, firstly to obtain the red colour change from the amber, and finally to reheat the very top of the glass to get a beautiful violet blue."

Now suppose that around 1900 Thomas Webb's management was shown the interesting graduated colour change that could be achieved by blowing cased glass of two colours into a tubular mould.    And that it could be done again, producing any combination of graduated colour changes.   They came across a particular combination of blue cased in ruby, and then the process was repeated with the outcome cased in amber.   It was attractive, the layers did not split apart when broken, and if made thin enough with a carefully finished rim, there was no way of telling what process had been used.   So the management proclaimed this amazing new glass invented by their brilliant research team, which involved reheating twice to obtain the colour effect.   Quite true, if a little misleading.    Had they told the whole truth, every glassworks in the world would have been copying it within a few months.   By creating the impression that it was a new special glass, they were able to sell it as the exclusive range Alexandrite.

Am I a million miles away or not?   Probably I am, as I have been wrong many times before.   So, could some kind person please explain what is wrong with my theory, and why Webb's really produced a new special glass when they had all the coloured glass and skills already available, just waiting for Alexandrite to be made.

... and does this help attribute my thorn vases?

Bernard C.  

[Leni]

Now suppose that around 1900 Thomas Webb's management was shown the interesting graduated colour change that could be achieved by blowing cased glass of two colours into a tubular mould.    And that it could be done again, producing any combination of graduated colour changes.  

Bernard, I'm not sure if you saw my earlier post about my two-tone vases http://tinypic.com/dyx3xt.jpg

I think these were made by the technique you describe above  :shock:

Having seen your thorn vases at Cambridge 'in the glass' :wink: I would reckon they were also made the same way, as you suggest.  Do you think they could be 'related'?  :shock:  

Leni

[Bernard C]

Leni — Your vases are the other way around.   With both my thorn vases and Webb's Alexandrite, the intense bands of colour are at the blowing iron end or top of the vase, fading away towards the bottom.    Your vases had the contrasting colour added as a casing of just the end at an early stage in manufacture, so subsequent casing and the process of mould-blowing to shape would have caused the edge of the contrasting coloured glass to blur.   With my vases the contrasting colour is there all over the inside surface of the vase.    It has just been made so thin towards the bottom end by the way that glass moves under pressure to fill a tubular mould that it seems to disappear.

Apologies for my rather poor explanation.   Perhaps an experienced glassmaker would explain it all rather more clearly.

Had we had this discussion last week I could have shown you the effect on my ribbon cloud 278, where a flat spiral of amethyst glass was dropped onto the uncoloured gather in the bottom of the mould just a fraction of a second before the plunger arrived.    It graphically illustrates how a thin surface layer is distorted as the glass is forced into the extremities of an irregular mould.   Here an original spiral, about ¼" wide, is spread around half the rim, a distance measured around the circumference of about 11".   This is surface spreading in both directions, so the thickness of the amethyst layer at the rim is only about 0.05% (1/2000) of the original.   However, unlike the ruby layer in my thorn vases, amethyst is such an intense colour that it never disappears completely, so you can always see a hint of this colour on about half of the rim of all examples of Davidson ribbon cloud.   I would add that "ribbon cloud" is our name for this rare, probably experimental decorative technique, we don't know what Davidson called it, and it is not really cloud glass, although it only occurs in the same colour combinations on the same products.

Phew, that's all!

Bernard C.  

[Leni]

Phew, that's all!

All!  :shock: It's fantastic, Bernard!  I'm sure no experienced glassblower could explain better  :shock:  

Thank you very much indeed!  

Leni