Green Glass is NOT Vaseline Glass
inJuly 14, 2008 - 12:05pm
Vaseline glass is a peculiar yellow to yellow/green glass that will fluoresce. When exposed to ultraviolet light it glows a bright green color. This bright green color can only be observed while a piece of Vaseline glass is under UV light.
Made 1840 to the present. 'Vaseline glass' is not a term that properly references any colored glass that may glow under black light. 'Vaseline Glass' is always yellow to yellow/green in color, by definition. Similar in color to its namesake, 'Vaseline.'
If Uranium particulate is included in the batch material at the furnace, any color of glass will fluoresce under illumination by a blacklight, which includes only the ultraviolet or UV spectrum. Other colors that may also ‘glow’ include opaque white, Custard, Burmese; a clear red, blue or green, and even some totally colorless glass. Those colors of glass are not 'Vaseline'. They merely fluoresce.
The amount of Uranium found in most types of fluorescent glass is not considered harmful in its solid, undamaged state (for instance, you wouldn’t want to abrasively polish a piece and inhale or swallow the small particles released). But any type of glass that does contain this radioactive material is mostly referred to by collectors outside of the United States as ‘Uranium glass’ and not ‘Vaseline glass’ (even if truly ‘Vaseline’ in color). Dealers who believe it helps them get more ‘hits’ to use the incorrect keyword of ‘Vaseline’ to describe their not-Vaseline colored glass aren’t helping themselves as much as they probably think. Misuse of this keyword generally only has the effect of drawing Vaseline glass collectors who mostly will be disinterested in a non-Vaseline color of glass, while simultaneously failing to attract a large collecting body for other-than-Vaseline-in-color Uranium glass buyers located elsewhere.
‘Uranium Depression glass’ would be a phrase of much better use for fluorescent glass items that date to the Depression era, and it would be entirely accurate. But copying incorrect identification keywords that other people on the Internet seem to be using may be easier than researching an item more thoroughly in order to employ useful, market specific terms.
A search of the well-known antique websites for ‘Vaseline glass’ has shown that many, many glass items are currently being inaccurately identified with the keyword ‘Vaseline’. We do understand that there will often be some variance in the depth or intensity of the greenish cast to the yellow coloration of an item that can properly be referred to as 'Vaseline Glass'. But colored Depression era glass that is green to the naked eye and also happens to glow under blacklight is not definable as 'Vaseline' simply because it glows. Though green Depression era glass contains Uranium oxides, the formula used to make it also included iron oxide. It was made with an entirely different formula than that used to make Vaseline glass.
So, remember, green is not the natural, visible color of Vaseline glass. Depression glass that is naturally green is just green Depression glass. Or it can be referred to as ‘Uranium Depression glass.’
The proper terms for describing Uranium’s glowing effect is ‘fluoresce’, ‘fluorescent’ or ‘fluorescence.’ Items that are not ‘Vaseline’ in color can best be referred to as 'Uranium,' or 'Fluorescent' glass (or Fluorescent Uranium glass), but unless the body color is actually ‘Vaseline’ in hue, use of that term misidentifies the glass. It should not be included in a Ruby Lane listing to describe an item that is not Vaseline in color as doing so constitutes employment of keyword spam.