Recently Purchased Cut Glass Vases

I purchased these glass vases at an estate sale. The vases are all 12" tall, clear glass and ring like a church bell. By accident two clanked together and the sound they made was unbelievably loud, clear and held for some time. They are heavy...vases are between 5-5 1/2 pounds each.

Does anyone have an opinion as to their age or type of glass. None of the research I have done has convinced me of anything.