Topic: Clear and Opalescent Uranium Vase.

[NevB]

At 7.5" tall this is larger than the usual pieces of this type. It is very thinly moulded with vertical, slightly twisted vertical optic panels, and it rings beautifully. The foot is a bit wonky with a swirl on the pontil of what appears to be opalescent glass. The body has a few bubbles and lots of seeds of probably colourant. The ruffles almost look like pearline, the rim is clear yellow. I'm reserving judgement on the maker.

[neilh]

These were at the cheaper end of the market, so you are probably looking at a lesser Stourbridge name, or Burtles Tate. I'm sitting on a few adverts from this era and there were a number of firms making items like this, I don't believe it is possible to assign them. Density can be variable as well due to chemical mix, but if it's English I would expect in the range of 3g/cc to 3.3g/cc

[NevB]

Thanks Neil, it's not the best made piece but that adds to its quirkiness. Allowing for the inaccuracy of my measurements it weighs 420gm., 300gm. suspended in water, so a density of 3.5. The measurements were taken with the same set of scales so the ratio 420/120 should be quite accurate.

[cagney]

  That swirly pontil brings to mind a piece I have with similar pontil. I have always been curious as to why/how this was done. Your piece tells me something about mine. The opalescent on yours tells me it was reheated, probably by a single flame after cooling some. I would posit that the connection reheated and twisted/spun off instead of the usual crack off method. Nice photos, like the wear pattern clearly shown on the foot.

[NevB]

Thanks Cagney, I would guess that it was actually snapped off and then rolled on a bench, using a tool to smooth it. How the opalescent glass got on the base is a puzzle though. As you say the opalescent part would have been created by reheating, my other guess would be it was then dipped in the clear glass to add the clear rim before the ruffles were formed. The photos make the colour a bit pale, overall to the naked eye it is a lot richer.

[Ekimp]

I would think the swirl mark is similar to a shear mark, usually T or J shaped, from where the blob of glass used to form the foot was cut off. Presumably instead of shears, they twisted the glass to remove what they needed.

Nev’s vase would have been held in a gadget so no pontil rod to obliterate the swirl. It looks like Cagney’s glass might have remnants of glass (on top of the swirl) that was used to attach a pontil rod, but the rod broke off very cleanly not leaving a scar.

[cagney]

  The use of a gadget makes perfect sense and Ekimps version is most credible. He is also correct that there is evidence of the use of a pontil rod on my piece. About a 3rd of a circle of sharp remnant. NwvB's use of the word pontil through me off a bit. I assumed there was evidence, we just could not see it in the photo. My understanding of how the pontil rod was used is that generally a small glob of glass is attached to the end and then attached to the piece to be worked. Sometimes the rod may be heated and attached directly to the piece to be worked I think. Leaves a brutal scar and maybe even a iron transfer from the rod. Plausible given these photos?

[Ekimp]

I assumed they used a blob of glass too. Your latest photos, Cagney, definitely look to show some iron transfer but maybe there was also a blob of glass that spread around the side of the rod, causing the big scar. I don’t know, but I imagine heating the rod to melt the glass to attach the rod could cause all sorts of issues.

It’s interesting that the swirls on both Nev’s and Cagney’s glass look the same. You can see they twisted one way by about one rotation, then changed directions until the glass separated, must’ve been a knack to it

[cagney]

  I really don't know either. Probably have to ask a glass blower, probably say " why would you do such a thing". Pretty sure it is an iron transfer as it rust and a magnet is attracted to it. Thanks for your input. Much appreciated. Of the few first hand accounts I have read from the 19th c. The skill and knack of a production gaffer/shop was somewhat mesmerisiing.

[NevB]

Just to add the foot on my vase was made separately and applied to the base of the vase. This would explain why it is a bit misshapen as the feet were often made by lesser skilled workers or apprentices. I've seen it on other pieces but with this one in particular when held up to the light, the opalescence turns to amberina.