Exhibit Antiques has dated this piece to the Georgian era.
An exceptional 18th century air twist ale glass dating to c1745.
Conical folded foot.

Historical Context
The Ale glass is ‘drawn’ to form the bowl and stem from one gather making it a two-piece glass, the join being at the base of the stem. Air twists were at their peak in c1750 by which time very few had folded feet. This example with a particularly wide fold, is earlier, 1740-45.

Date & Origin
England, c1745. Period of King George II.
Condition
Excellent. No chips, cracks or restoration.
Dimensions
Height: 20.6 cm.
Rim diameter: 7.2 cm.
Foot diameter: 8.3 cm.
Weight: 260 grams.
Articles

If you would like to learn more about 18th century air twist glasses, we have an excellent article explaining all the difference with supporting
Identification of Antique Drinking Glasses | The English Air Twist
Exhibit Antiques has dated this piece to the Georgian era.
Specialists in 18th & 19th century antique glass
You can view the stock and full dealer information on the Exhibit Antiques Profile Page