This is a superb antique wine glass.
Heavy cut crystal.
French Saint Louis crystal from the Nineteenth Century.
(No mark before 1936).
The famous pattern TRIANON created in 1830.
Still for sale in Saint Louis crystal factory shop.
(price: 160,00 euros for one glass.)
Height: 10,8 cm
Diameter: 6,2 cm
Period: XIXth Century
Here is a converter inches / cm to help you with the dimensions: