Topic: Glass vase with applied trails/feet; Harrach or S&W? Other?

[Galle]

Has anyone seen anything like this? The applied feet wrap up around the piece and merge into the rim and are amber, blue, and green. There is some uranium in the green and blue, and some amount of (manganese?) in the amber, because under strong black light, the blue and green glass glows green (slightly) and the amber glows orange (slightly).

[Lustrousstone]

I doubt there is any uranium in your pretty little vase, uranium never glows faintly. Faint green may be manganese and I think orange is cadmium. That blue and amber combinations seems common on Harrach items

[Galle]

Hmmm I never thought about that (the uranium issue)... I just never realized that any other thing caused a greenish glow.

[TxSilver]

I often see these types of pieces called Moser Harrach. Personally I believe yours is Harrach. The amber is paler than many of the vases, but the stems and flowers look Harrach to me.

[Galle]

Thanks, Anita - I've been leaning towards Harrach myself. I didn't know if S&W ever did anything similar.

[krsilber]

If it were just a little uranium, might it not glow faintly?  Although I've seen green glass formulas with manganese, it doesn't seem common, and the colorless Bohemian glass I have doesn't glow green.  I don't know if that's because they used different decolorants or what.  The colorless glass I have that glows green rather than a yellowish green glows really quite faintly; I'm not sure you'd be able to even see it in green glass.  You can only add so much manganese before you start getting purple.

The glow color of glass is probably more complex than many glass enthusiasts (myself included!) have made it out to be.  There are so many confusing factors, such as multiple fluorescent substances and the role of absorption of light by some materials.  You could have one substance emitting light and another absorbing it.  Or contamination could influence things, as in this little snippet from this article:
"However, there was a problem, most known fluorescing metal oxide dopants [I wish they said what they were!] failed to produce fluorescence in our  glass. This turned out to be caused by impurities from the ingredients used to make the glass and from the  inexpensive silica/alumina crucibles we were then using."

Geez, I see a quick mention of fluorescent glass, and can't stop myself - blab, blab, blab!

[Lustrousstone]

No Kristi, the uranium glow is quite distinctive but quite difficult to describe. It's almost like the difference between an LED fairy light bulb and an old fashioned tungsten one. The two greens are quite different shades, so even if the the level of uranium is low you can tell the difference (what you see with lower levels of uranium is perhaps best described as a colour wash rather than thick blob; you know it's the same bright green colour). Even with an LED light you get a reaction 2ft away. For the faint green glows you have to get up close and personal and possibly in the dark. Green and flint (clear) glass that has the faint glow is not uncommon here in the UK but it is often early/mid 20th century stuff. I spend many happy hours checking stuff out in my searching.

If Galle's green contained uranium, I would expect a bright glow for that shade; if the blue contained uranium you would be able to see a hint of green in the photo. It is just too blue.

Hope this makes sense  :spls:

[krsilber]

I have uranium glass and know what the glow looks like.  Pieces from Dave Peterson's collection vary in intensity.

Green and flint (clear) glass that has the faint glow is not uncommon here in the UK but it is often early/mid 20th century stuff. I spend many happy hours checking stuff out in my searching.

That's interesting, I've often wondered about that.  Is it a green glow or a greenish yellow?  What about older English pieces?

[Galle]

I'll see if I can capture the effect with my camera - it's a little tricky.

[Galle]

I also wanted to say regarding the glow that I have noticed that Loetz Creta glass (Creta Rusticana, for example) has the same type of "slight" glow - if the black light is held right up to the piece, you can see a distinctive glow, but it is nowhere near the brightness of, say, Oceanik.

I also have some examples of clear or slightly purple glass that produce the same effect - nothing from a distance, but up close, the green starts to show.