Thanks Pamela,
i think its just 2 layers, theres a beveled polished edge, which may look like a third.
Ive been in contact with Warren Galle, (thks

)
he is doubtful about Bohemian, loetz, Poshinger, and thinks i should look to an English maker,
Im thinking Thomas webb, or Stevens & Williams,
anyone? Its certainly looks the same as the great glass example, above, but they are not sure either

Is the cased or Uranium a clue?
(Warren, jjust curious, were loetz ever Uranium?)
Cheers all,
Andy