Topic: Blue Uranium Glass Butter Dish?

[NevB]

This is the first piece of blue uranium glass I've found. The colour is a deep turquoise but it doesn't photograph perfectly. I think it's possibly American but having trawled through the EAPGS website and the other usual places I can't find it. I assume it's a butter dish.

[Lustrousstone]

It's a butter dish but neither the shade of blue (I'd expect a greenish hint) nor the glow look right to me for uranium.

[NevB]

My Geiger counter tells me uranium.

[Lustrousstone]

Your Geiger counter just tells you there is radioactivity. Other things are radioactive...

[Paul S.]

certainly in that last picture, there is a lot of greenish colour showing through the blue.           Originally, Annagrun and Annagelb - for example - were names given as a consequence of the green and yellow appearance of glass where uranium was added deliberately for the colour effect it produced, and the bulk of uranium glass made since then has used uranium for just that reason.           In view of this reasoning then why it might be used here in what is to all intents and purposes a blue glass seems odd - perhaps this shade of blue can't be produced without including uranium, though I'm sure I've seen this blue many times without uranium  -  didn't Davidson make a blue of this hue?   
I could be wrong, but there looks to be a slightly overall blue cast to all of these pix?

I'd agree with butter dish  -  all these similar things with built in underplate, and lids, are likely butters.

[NevB]

As I said, the intensity of the blue is not reproduced in photos. As you speculated Paul, from another piece I've seen in this colour it was said a small amount of uranium was added to produce this intense colour. That was a piece of American glass and I don't see any reason to doubt the information. Here's another photo which I think shows the glow better. The blue colour totally disappears under UV.

[Paul S.]

I'd never thought of it before, but assume that in coloured glass, such as this piece, manganese would never have been included ??

[NevB]

I don't know but it's possible manganese was added to the initial batch of glass to produce clear glass before colourants were added later. Manganese was only added at 0.5-1.0%, adding more than that produced purple glass. IMHO the glow of this piece is too intense for manganese.

[Lustrousstone]

Manganese was often added to coloured glass in my experience

[rocco]

I cannot really comment on whether the piece in question is Uranium glass or not, but I noticed that the blue Sklo Union pressed glass items show a strong yellow-green glow under UV (see pic).

Michael