Crystal cut glass Pedestal Stands (2)

Hello. I purchased these from an estate a couple of months ago, and was just amazed at their beauty. This is a matching pair of Crystal hand cut pedestal pieces. They are 8 1/4" wide by 7" tall. These items came from a well to do family that were descendants of John Adams. The house was full of beautiful Federal Furniture pieces, some of the items were pre Federal dating back to the 1600's. There was a hand written very brittle old note card with these pieces that read as follows, (the name has been partially covered); "Very Early American Glass, Has Value, from Burlington Flats". This family was originally from the New York, and Martha's Vineyard areas. Any help or ideas with this are very much appreciated. I am lost as to the time period, makers, or potential value.