Glass Message Board
Glass Identification - Post here for all ID requests => Glass => Topic started by: RoynMargaret on June 18, 2007, 09:58:02 AM
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http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7536
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7535
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7534
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7533
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-7532
All were photographed in natural daylight without flash. The only one I am confident of is the candlestick. I am reasonably confident that all items date from the 1930s - 1950s.
Any additional information about makers/designers would be gratefully received. I originally attributed the pedestal bowl (10-in diameter) to Sowerby, but now have some doubts.
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Ive found its impossible to tell unless I have my little mini blacklight with me. I have seen some gorgeous pieces of glass and been positive they will glow, only to find they dont. Even those with a seemingly daytime glow to them.
I also have a flower set which is the lady, frog, bowl and two matching side bowls. All look identical, frosted green...only the two bowls have no uranium in them at all and the rest glows like the blazes. I was very disappointed when I bought the set, believe me. So....I dont know how you actually can unless you had a counter :)
Trudy
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Selina - I could get a mini blacklight, but thought they were expensive - can you direct me to a source please?
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I'm not bad at it
1. probably
2. No
3. definitely
4. No
5. No - Sowerby uranium is a yellow green, this is later non-U Sowerby
Halfords sells a UV kit for oil testing. It's a pen light with good UV levels (tried and tested) (and orange goggles so you can play CSI) at £5.99, relatively expensive but no postage and effective. A worthwhile investment if you're selling, as U glass attracts a higher premium. Don't forget it must be a very very bright green glow and that colours other than green/yellow may contain uranium. If the glow is pale and fuzzy and you can't see it in daylight then it's not uranium. It's also the quality of the glow rather than the quantity.
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You can get the mini lights cheaply on ebay...sorry for the big link but that gives you a few lowest priced ones...
http://search.ebay.com.au/uv-light_W0QQcatrefZC6QQcoactionZcompareQQcoentrypageZsearchQQcopagenumZ1QQflocZ1QQfromZR10QQfsooZ1QQfsopZ3QQftrtZ1QQftrvZ1QQga10244Z10425QQsabfmtsZ1QQsacatZQ2d1QQsaobfmtsZinsifQQsaprchiZQQsaprcloZQQsaslcZ2QQsbrsrtZd
I have also bought the kids UV pens that they use for invisible writing..they are usually under $10. The one I take out is a little one on a key chain..its enough to hold the piece in your hand, half covered...and shine the beam into it.
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I do think buying yourself a blacklight would be a sound investment, and they can be very cheap. The one I use is intended for seeing hidden marks on stamps for stamp collectors.
Without a blacklight it is easy to make mistakes about whether glass contains uranium. Some glassworks made some designs over a long period, using uranium in the years before about 1940 and other coloring agents after the war, so you can easily get a set that has some items containing uranium and some not. They may even have been kept in storage for years and sold as a mixed set originally.
The only one of your pictures I feel sure I can identify is the last one, the large pedestal bowl. Sowerby definitely made that design, although I think it may have been copied by some other glassworks.
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Thanks for all that.
Looking at the adverts, some of the "keyring" and small torches appear to just have LED bulbs. I have a webcam with LED lights - but can't get the room dark enough until night time to test whether they make anything glow :)
Alternatively: Would this be good enough? It's cheap and so is the postage - and not a million miles from my part of the world :) There are several other apparently similar items at around the same price or even cheaper.
http://tinyurl.com/2h4da4
The only one previously that I had any confidence in was this at £12.99 + £6.99 P&P, so there is quite a price differential for something I would rarely use.
http://tinyurl.com/24tfez
I like bright green glass and buy it anyway, not because it is uranium, but it's always nice to know - I have picked up on the added value aspect 8)
I am somewhat relieved about the large bowl - I had identified it as 1933 Sowerby, then started to have doubts.
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If you cannot say that it is uranium with an LED UV light in daylight then it's not uranium! If you hold the torch close to the glass and turn it on you should either see a bright green beam in the glass in clear glass or a bright green blob in translucent/semi-opaque glass. A larger UV torch really is not necessary for ID purposes. I collect uranium glass and only ever carry a UV torch with a single UV LED. As I keep reiterating, if you cannot see the glow in daylight (semi-shaded if bright sun) then it's not uranium. The pen you show would be fine
Your webcam seems, to me, to be unlikely to have UV lights :)
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LOL I meant the camera lights will not come on at all until a ceratin level of gloom is reached. I was fairly sure they were not UV LED bulbs, but I'm still learning.
One of my concerns is to be able to capture the glow in a photograph, hence my looking at relatively large UV lights
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Roy I carry one of those penlight types in my bag always and it works fine whatever the light level. Mine was £1 in a cheap shop but places like WH Smith's have them as well... marketed as spy pens for kids, or security pens for grownups. :)
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A question has long puzzled me and here seems a good place to ask it. Why is everyone so interested in whether or not a piece of glass contains uranium? No one ever asks if a blue glass is just cobalt, or does it also have copper in it, for example. Surely GMB members are sufficiently adult not to be bothered about radioactivity? Is there some kudos and/or increased value in a uranium piece?
The last picture on the list, which Angela correctly identified as Sowerby (2505, I think) is an example of one where we made large numbers using chromium/iron but there would almost certainly be others, from a different era to mine, which also contained uranium. So what?
Adam D.
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Adam, I think it's just that they display so beautifully under blacklight.
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When I had a museum of glass in the centre of Paihia a few years ago we had some recessed black-painted display boxes with UV lights (carefully shielded so the light didn't shine in anyone's eyes) and displayed uranium glass there. There were switches so you could change from UV light to ordinary light and see the difference. It did make quite a dramatic display and people did like it.
(Since I moved my collection to my studio I've set up the black boxes but haven't fitted the UV lights. So if any of you are coming to Paihia NZ and want to see this part of my collection, give me plenty of notice so I can get the lights fitted in time!).
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RoynMargaret:
the reason people want to know if it has uranium is they don't want to get stuck with yellow glass that does not do tricks!! people love the part that it does tricks, as it is such a big change from daylight to blacklight.
Here is the kind you want: look up ebay item # 130126461722
It ships world wide, it is cheap, it works (i have several) and you can shine this little flashlight across the room and light up a piece of uranium glass! it will also shine through well lit display cases in an antique shop and 'show the glow' where the tube fluorescent ones will not work (the light gets washed out from the lighting in the display case).
IF you don't have a UV light source, take the piece out into bright, direct sunlight. if it glows a bright green (or at least, looks a lot brighter than indoors) it has uranium in it. it is catching UV rays from the sunlight. if you have a digital camera, use the flash feature, and when you look at the picture, the uranium version will look brighter than the non-uranium green glass.
the UV LED is made to register a certain area on the light spectrum. if it is not advertised as a UV, it will not do a thing. LEDs are made for different purposes.
Dave Peterson
Mr. Vaseline Glass
p.s. see my posting on 6/18: blue AND uranium glass! for a photo under UV of a very special piece of uranium glass.
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Many thanks for that Dave. I am trying to buy the little torch but have had to e-mail seller about shipment to UK since his auto checkout rejects my (confirmed) address. It certainly looks the most workmanlike and best quality of all the varieties on offer and at about a fiver GBP incl. P&P, cheap enough, especially because I can use the same rechargeable AA batteries I use and have lots of :)
Meanwhile, what a super thread this is turning out to be.
I had a look at your lovely blue and uranium vase. Can you please tell me how you photographed the "green" version? i.e. was it in a completely black box, what size of UV lamp, what exposure (I assume automatic camera features will not work in blacklight) etc? I am still contemplating the 45cm (18-in) version linked in my earlier post.
Re:your comment about flash. I used flash for general glass photography but got unacceptable reflections and better results from natural light in a translucent white box - which is how all my OP pictures were taken. So, how should glass be staged if using flash?
If there is a link to a thread about photographing glass I shall be grateful.
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RoynMargaret:
the comment about using flash was just to see if there was uranium in the glass to 'tickle' the electrons (which is what makes it turn bright green). As far as photographing glass, a tripod is a must.
Here is my very simple photo layout:
http://www.vaselineglass.org/leftwall.jpg (http://www.vaselineglass.org/leftwall.jpg)
it is black velvet on a shelf. I put a big UV fluorescent strip above the piece of glass (hand held, about 20 inches long) and have the camera on a tripod. I have a dark room. I push the button. that's it. If the photo needs to be tweaked a bit, I do that on photoshop. I don't use flash, I use regular room light.
Here is a photo that I did use flash, just to show the different effects a flash, room light, and blacklight has on a piece of uranium glass:
http://www.vaselineglass.org/webbtallbl1.jpg (http://www.vaselineglass.org/webbtallbl1.jpg)
You will notice that the flash makes the top opalescent rim show up with more clarity (the first thing I noticed when I took the picture). But, if you look at the stem on this piece, you can see that the flash picture (especially down where it meets the brass base) is a brighter green. This piece is almost clear glass in room light, and it was only due to that little bulbous knob at the base that I even decided to test it with a blacklight when I bought this piece. It has been a favorite piece of mine ever since I got it. both the flash and the blacklight photo was taken with a black velvet background. the far right photo was done using a roll of duck cloth/sail cloth (light, white canvas, that I keep on a roll to keep it from wrinkling)
Mr. Vaseline Glass
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Thanks for all that. You are most generous to share your expertise. I am severely disabled and it may be some while before I get around to experimenting with UV lighting set ups, but, since it is my hobby, I think I will spend the money, get the kit, and post any results.