Exhibit Antiques has dated this piece to the 18th Century.
A fine 18th-century dram glass.
A very nice example example.

Date & Origin
England, c1740. Period of George II.
Condition
Excellent, age-related wear as shown. No chips cracks or restoration
Dimensions
Height: 8.2cm
Diameter: 4.6cm
Foot diameter: 5.3cm.
Historical Context
As of the start of 1760, the Gregorian calendar was 11 days ahead of the Julian calendar, which remained in localized use until 1923.
Exhibit Antiques has dated this piece to the 18th Century.
Specialists in 18th & 19th century antique glass
You can view the stock and full dealer information on the Exhibit Antiques Profile Page