URANIUM GLASS is a speciality amongst glass collectors. The
uninitiated might be interested to know that yes, it really is uranium
but no, it isn't dangerous. There is a lot of information from uranium
glass collectors on the web: try Googling it. Uranium was used as a
glass pigment in the 19th & early 20th centuries - & even then there
were alternatives & it was expensive. Nowadays, except for
reproductions (primarily Czech) & occasional artisans, alternatives are
Uranium glass is usually superficially yellow or green glass but can be
other colours. What identifies it beyond dispute is its VIVID GREEN
FLUORESCENCE when illuminated by UV. It is easy to buy cheap UV lights
& torches on eBay nowadays.
This tazza (copyright reserved) is shown with & without UV illumination,
to give you an idea of what it should look like:
The problem is that other minerals produce fluorescence under UV, too:
orange, blue & dull insipid green, for instance. The difficulties
from the buyer's point of view are these:
A seller describes untested glass as uranium because they can tell 'by
eye'. Reject such opportunities! This approach involves guesswork &
the only way to be certain is to test it.
A seller produces photos showing fabulous bright blue (or dull green)
fluorescence & calls it uranium: it is NOT. In most cases this is a
genuine misunderstanding but some sellers persist in promoting these
colours as Uranium Glass, despite ample information to the contrary.
A seller imagines that because much, for example, Bagley green glass
contains uranium, all glass of that pattern is uranium glass: it ain't
necessarily so! WW2 resulted in government appropriation of uranium
from Bagley (& others, presumably) & alternative, almost identical,
glass was then produced using different colourants. The English Bagley
glass company is notorious for lengthy runs of particular designs (a
policy which was ultimately to prove its downfall) & their ranges can be
uranium - or not. A UV test is essential &, in fact, can be used to
pretty well determine time of manufacture as pre- or post-war glass.
So beware & be informed. Uranium glass can display fantastically on a
sunny windowsill, where the UV of natural sunlight can induce the
uranium to fluoresce that astonishing green - but it can't if there is
no uranium present.