Hi Sheila,
After years of collecting, I just knew, it is difficult to explain.
Books are a great resource once you have decided what type of glass you want to collect, be it by country, factory, designer, etc.
I found I was drawn to glass from Finland, mainly, but also Scandinavian glass, mostly from Sweden.
The forums here are a fabulous aid too, but not always easy to navigate if you don't know what you are searching for.
Never be afraid to post and ask. Even I am still learning

If you get a suggestion, have a search through Google and you may see a piece identical to yours.
I spend hours searching sometimes and it can be so very frustrating, but also incredibly rewarding once your mystery is solved. I have pieces, signed too, that I still cannot identify, but I can't help but keep collecting. I could open a glass museum with the pieces I have here, pieces from all over the world. If I like a piece, I buy it (money allowing) and I'm supposed to be scaling down in order to move

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