Glass Message Board
Glass Identification - Post here for all ID requests => Glass => Topic started by: brucebanner on October 22, 2016, 01:29:17 PM
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I have come across this several times (i think only in uranium glass so far), described as a bad batch of glass in real trouble of disintegrating, this one shown has a very rough almost flaking of the glass to the outer surface stem, foot and underside of foot with a rough texture. The inner bowl is unaffected lovely and smooth as is the decoration which is smooth with no crackling, i'm wondering if its a treatment that causes this problem?.
In UV the uranium is very patchy almost to the point you think it has rubbed or flaked off in places.
4 7/8th inches in height, 2 3/4 inches across the rim and 2 1/2 inches across the base.
Regards Chris
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picture of the uranium.
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???
How very odd. I cannot imagine what might be giving rise to the appearance of uranium, which is physically in the glass, seeming to be "patchy".
If it's there, it will glow under UV and the glow will distort details in pics, it emanates from the thing.
Is it possible there could be something there absorbing the UV light? Dirt embedded in the cracks?
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How is that pattern applied, is it needle etched or something?
And how old do you think the glass is?
m
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I would say the glass is late 1880's- 1900, its lost its lead crystal ring probably due to all the cracks, it looks like my photo's close up in real life so it's not the camera, i did have a blue mould blown vase with the same problem but it's been recycled, it was listed on Ebay but had not interest along with a uranium glass one probably 20 years older than this one, it does not explain why the bowl inner surface is fine, if it was a glass mixture problem the inner bowl should be falling apart as well.
I would say its wax etched not machine as machined is a lot clearer and uniform.
The third picture shows more defined machine etching.
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so it has been coated? or cased? and the cased glass layer was uranium glass but is the layer that is crizzling maybe?
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I suspect the blue under UV is the alkali leaking out of the glass and blocking either the UV getting in or the emitted green rays getting. I don't think uranium glassware is ever coated, unlike ruby stuff. Storing the glass upside down with less contact with damp air probably explains where the crizzling has started.
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Thank-you Your Editorialshipness, 8)
I was sure there had to be a logical explanation. It's been bothering me. :)
The pattern does look a bit like one of the more unusual ones from a series like the "Pall Mall" sort of decor of etching.
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That's a much more probably explanation than mine Christine. Very intriguing.
Would it have been a bad batch though to start with if it's started crizzling, but just that the interior was kept sheltered from attacks on the surface?
Sue I was thinking of the 'Pall Mall' things as well. Possibly from a similar era perhaps?
m
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Yes, it would have been a bad batch but damp air encourages crizzling
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"A study of deteriorating glass" from one of the " A Guide to Sandwich Glass " books. Too much typing for me. Photo paragraphs read in order.The best information I have found on the subject.
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complete photo series
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I recently sold a couple of wine glasses, early Victorian, in uranium and only the cut sides were affected and the underside of the foot, the seller left feedback and i tried to look into what it said but it was way too complex.
I had a third but it's in my dads kitchen as they have gone all green.
"Excellent items - interesting "fission track" markings on polished surfaces!" (Ebayer comment).
Similar wine glasses as below.
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Another example, pressed glass c. 1880's, Pittsburg, USA. Surface rough and somewhat "sticky" to the touch.
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This time a French perfume bottle, late 19th C. Some of the metalwork was corroded too, stored somewhere damp would tally. From memory I think one side was more badly affected than the other.
John
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I know from my mechanic days the fat from fingers and grease reacts with tungsten glass when heated to weaken the glass that's why your not to touch the glass on bulbs, i wonder if some chemical or the acid from wine etc starts the process off, or are there different forms of glass breakdown, if a batch of glass is bad why be in certain places and not others it makes no sense it should be widespread not localised. If it was damp then why are bottles buried or found in rivers not effected, i reckon it has something to do with light and heat like the tungsten bulb theory.
Your bottle John do you think could be bad on one side due to it's position in light maybe sat on a shelf for years without moving?.