Set of six glasses of La Granja, late 18th century-early 19th century

Set of six glasses from La Granja, late 18th - early 19th century.
Glass.
Accompanied by a case (11 x 10 cm).
They show wear due to use and the passage of time.
Measurements: 10 x 8.5 cm; 9 x 7.5 cm and 8 x 4.5 cm.
Set made up of six La Granja glasses of different sizes and decorations. All of them have a golden fillet on the mouth.
The Royal Glass and Crystal Factory of La Granja was a royal manufactory founded in the Royal Site of San Ildefonso (Segovia) by Philip V in 1727. Its first director, and therefore founder, was Buenaventura Sit, who with funding from the crown created a small furnace for the manufacture of flat glass, in order to supply the Palace of La Granja with windows and mirrors. This type of large flat glass was very expensive at the time, so it was more economical for the crown to set up its own factory rather than import it. In fact, this need for large sheets of glass led to important technical research that culminated in improvements in the casting technique in 1737, which enabled glass larger than 3.5 x 2 m to be made. Production was extended to artistic glass in 1746 with the arrival of the French master glassmaker Dionysius Sibert, who introduced lead to create glass. Shortly afterwards, in 1750, the German Juan Eder began the manufacture of inter-fine glass, using potassium-based glass instead of the traditional Hispanic sodium-based glass. These potassium glasses were brighter and more resistant, allowing a higher quality cut. Finally, in 1836, the Royal Treasury officially took over the facilities.