Christine I'm a bit skeptical with 36 years of glass collecting/selling experience, athough granted the vast majority has been US based art glass, that the basket/bowl is relatively recent. It has all the earmarks/traits of items produced (whether English, French or Bohemian) during & up to the late 1800's to early 1900's. Now on the reaction to the blacklight, yes I agree it all varies with the chemical composition of the formula & I have seen/experimented with different reactions for years. Case in point: Henry Hellmers is considered by many to be the Godfather of American glass chemists (I won't bore by naming them all) & from 1930 to around 1955 Henry developed more than 1,000 formulas, many of which contained one or more of the reactive Uranium Oxides although in the early years they are simply listed as Uranium. The National Cambridge Collectors has a listing of many of his formulas & as an example a batch of light Emerald which weighs in at 1,422 lbs (US) only 2.68 lbs are reactive Uranium Oxides combined with Arsenic, Copper Oxide, etc. & the reactions vary formula to formula, e.g. a batch of Willow Blue that also contains the reactive oxides does not produce the same reaction under blacklight due to chemicals that differ in that particular mix. I've seen blacklight reactions that vary from the traditional greenish glow to yellow, orange, pink/volet, etc. I'm not a glass chemist, but I've often wondered what chemicals affects included in the mix causes what reactions? Why do compositions which may include, Bichromate, Copper Oxide, Red Lead, Borax, Manganese, Tin Oxide, Antimony Oxide, etc, etc, react differently when paired with the traditional Uranium Oxides? It's a question that probably only a scientist using a Spectrometer could answer, I can say though that I'm not suprised at seeing orange, pink/violet, or any other hues in what I've tested during the years. Ken