Topic: Uranium in Imperial Glass Co carnival glass - thoughts please

[Quackers]

Hi there, I have just taken delivery of one of the bright LED UV torches...and decided to run it over my Carnival collection.  I didn't think that I had any vaseline/uranium glass in the 130+ pieces that I have (except a modern toothpick holder) so I was rather surprised when a couple of bowls reacted brightly, particularly from the bases.  Both are 8" (20cm) bowls by Imperial, a Shell & Sand and a Scroll Embossed both in what I considered to be Teal or Aqua glass with a marigold type irridescence.

Shell & Sand
   http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7863
   http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7869
   http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7868

Scroll Embossed
   http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7866
   http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7865
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7864

Does anyone know if that is normal for that colour glass?  I would be grateful for any further information about the use of Uranium in carnival glass that is not typically vaseline coloured (strawy yellow-green - is that right?).

BTW I also discovered that my "plain" Sowerby Chunky bowl in depression green is in fact a very bright uranium glass       http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7859

TIA

[Anne]

Oooh isn't it fun when that happens unexpectedly.   The Chunky bowl is fab in uranium green - my mother has this in marigold carnival (kindly identified for us a while ago by Glen here on the board.)

[Glen]

I'll answer this query to the best of my abilities - but if anyone can help on the chemical/physical properties of the colorants involved, I would be very grateful.

Imperial made very limited amounts of "true" vaseline Carnival, however, we have found (based on examples in our collection) that Imperial's Helios and aqua/teal may also exhibit a somewhat duller and more "milky" green glow. From my own experience, I have observed that the glow from "true" vaseline (Carnival) is a transparent green and is very vivid indeed. The glow from Imperial's Helios and aqua/teal is not as vivid and is more translucent or cloudy in appearance. Maybe this was caused by manganese in the batch?

Some of Fenton's white Carnival also has a cloudy green glow; we've seen the same effect on their Florentine green (similar to ice green) too.

If you want some more fun with your UV light, look at red or amberina Carnival (old or new) or Summit's Geraldine's Delight Carnival (new). You'll possibly see an orange glow caused by the use of cadmium as a colorant.

I hope this helps a little.

Glen

[Lustrousstone]

The Sowerby pattern is very common in flint, green and carnival but I have yet to find one in uranium  . Lucky you.

[Anne]

Glen, I noticed that orange glow in my (non-carnival) amberina goblet's foot and wondered what caused it. Thanks for solving another mystery for me. 

[Quackers]

Anne - I really bought it to check for a glow from the clear crystal casing on my Whitefriars glass.  According to the "receipe book" from the factory this included a tiny amount of Sodium uranate for a while - so it might just be possible to distinguish WF cased items from the various scandi look-a-likes.  But I can't always see any glow...

Glen - many thanks for that   I would agree that the glow from the Scroll Embossed bowl is not very strong but the Shell & Sand is very bright.  Unfortunately I don't have any Vaseline prime carnival to compare it too   I haven't got any Fenton white or any red at all either for that matter   (would love a Peacock Tails bowl in white...)  Talking of very bright glow, I do have a modern Boyd toothpick holder and that really sings!  http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7861  You can just see my torch to the right. Thanks again.

Christine - I'm open to offers on the Sowerby bowl, it's in really pretty good condition (if you look really closely there is the odd tiny fleabite to the base and maybe a couple on the rim) hardly any wear at all though, just about 7.5" diameter.  Email me if you're interested 

[Glen]

Tim - it sounds like your Shell & Sand may well be vaseline Carnival. We only have one example of Imperial's vaseline Carnival (though we have a pretty good spread of other makers) and that is the Beaded Bullseye vase. It has a very vivid glow.

Some of the modern examples of vaseline Carnival are very strong indeed. Summit also did some hits-you-between-the-eyes stuff. About fifteen years ago we did an experiment with the help of a physics teacher in a lab. We took along a selection of vaseline Carnival and tested them with a geiger counter. The Summit toothpick gave one of the highest readings.

Anne - the cadmium glow is fascinating. In fact it's very appropriate for me to quote my source here, as it was John Boyd (of Boyd's Art Glass - see Tim's message above) who informed us that "there are several metal oxides that fluoresce. The only one that comes to mind that will flouresce orange in glass is Cadmium Sulfide. It is the only colorant that will make glass yellow. Actually, cadmium is one of the colorants that "needs" a reducing flame. But to help it to the brown side (topaz) I think I would add a pinch of blue, black Copper Oxide."

Glen

[Quackers]

Hi Glen, thanks for that - I'm not entirely sure that it is Vaseline   Did you look at the photo of the base, it looks very green/blue to me?  I have enough trouble working out the difference between pastel Marigold and Clambroth (Imperial Grape plate with a pastel type yellowish irridescence) so I'm likely to be quite stuck on this one...  It will wait.

thanks

[Lustrousstone]

I don't think your Shell and Sand is vaseline as far as Carnival colours goes BUT a lot of the green depression ware contains uranium. I can think of no reason why green variants of Carnival shouldn't. It wouldn't be called vaseline in the US, but it might here