For the most part these are usually attributed to Murano Glass, Which is not always the case but many makers in the Murano area makes this style. As for value, I may be able to pin point a value in a few days, I just posted one on shopgoodwill this week, It was a large one, but I am curious about what It will go for. I have personnally sold a couple paperweights in this style and got around $30.00, but they was for sure murano.