The World is Made of Glass Ltd. has dated this piece to the 18th Century.

The tumbler is in excellent condition for its age. This means, of course, that it shows age related wear and tear to the base commensurate with some 250+ years of use.
The tumbler is in the clear colourway and is 7.5 cm (3 inches) in height, 6.2 cm (2.5 inches) across the bowl rim and 4.5 cm (1.8 inches) in diameter at its base, the bottom of which carries a rough pontil mark. The bowl is moulded with five Lynn rings. There are no chips, cracks, significant scratches or any obvious evidence of restoration.
English lead glass weighing in at 90 g. (~ 3 oz.).
The World is Made of Glass Ltd. has dated this piece to the 18th Century.
Dealing in antique and collectable glass from the 17th to the 21st century.
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