This may not be the place to ask. Only mentors can answer in here so there is a limited knowledge bank and this part of the forum is for questions related to Ebay.
A quick google shows there is a range of specialist glass collecting forums - maybe try one of those?
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)
