Ho Norman,
I cannot recognise from the picture wheather the piece is really sheeted by copper.
I have found here 3 copper covered pieces, one piece is known Jurnikl Osaka Vase, two of them rather older Rudolfova huť designs.
From former employer of Rudolfova huť I have got information, that in 70ties had been made some experiments with this copper sheeting in this factory, probably leaded by Pavel Pánek. The same information had confirmed to me and Marcus Newhall also Mr. Medek, former sales director from Libochovice.
If it is really copper, it is probably one from this experimental pieces, it is quite rare. The technology how it had been made has been explained to me, but I am so poor in glas technology, that I did not understand it fully. Marcus, however understood and will be able to explain it, I am sure.
Jindrich