Objects of clear greenish glass of a paler hue than is made in the province of Almeria, decorated with blue, or some opaque colour (see woodcut); in some instances part of the object is decorated with a rough crackled surface.
Objects of opaque glass with different colours, vases, glasses, cups and saucers, of thin milk-white texture with blue spots, or imitations in the Japanese style of different colours. Vases for holding flowers, and other objects, of dark blue glass, milk-white cups, glass and other objects ornamented with lines of red or blue of a thicker paste than the preceding ones.
Although these objects are copied from Venetian models, they are coarser in every detail, they are heavier and thicker, and the delicate and elegant ornamentation which we find on Italian specimens is almost always wanting, we seldom find examples of the beautiful millefiori chalcedony or tortoise-shell paste, and the outline of these objects is symmetrical and Oriental in style.
The royal glass manufactory at La Granja de San Ildefonso, was founded on the remains of an important one which had been established some years before, under the protection of Philip the 5th, at the Nuevo Bastan, in the province of Madrid.
Towards the years 1712 to 1718, this king commissioned Dn. Tomas del Burgo and Dn. Juan B. Pomerague to establish glass-works at the Bastan; twenty foreign workmen were brought over with this purpose, with their families, and the necessary implements. These gentlemen did not carry out the undertaking to the king's satisfaction, and in 1720 his majesty gave Dn. Juan de Goyeneche special privileges that he might "make every kind of glass manufacture up to the height of twenty inches, and have these glasses worked and polished, embroidered and covered with metal; to make looking-glass and similar decorations, and every kind of glass vessels, and white glass for window-panes, and every sort of glass vessel of different kinds and forms which have been invented in the present time, or likely to be invented in this art." In order to carry this out, the king allowed them to have as many foreign masters and workmen as they might require, with the sole condition that a fourth part of the workmen employed should be Spaniards. It was prohibited that any industry of a similar kind should be established in Spain for thirty years, or that glass made abroad should be imported into the country.
After a long series of annoyances of every kind, Goyeneche succeeded in meeting with the king's approbation, but as fuel was very scarce at the Bastan, he removed the glass works to Villanueva de Alcorcon, in the province of Cuenca. From the ruins of this glass manufactory, Larruga says in his "Memorias," [vol. xiii., p. 274], "was founded the splendid glass manufactory of San Ildefonso."
Ventura Sit, a native of Catalonia, constructed an oven there, which worked from 1728 to 1736 with great success. Queen Doña Isabel encouraged Sit, and the king ordered him to make some glasses which might serve for mirrors. Those he made at first were small, but Sit began by making them 30 inches long and ended by making them as large as 145 inches. The machine for polishing them was invented by a Catalan called Pedro Fronvila.
The section of glass vessels of a superior quality began to work in 1771. Glasses, bottles, and objects of all kinds were made there under the direction of a glass worker called Eder, a Swede, and Sivert, a Frenchman. Another section where the same quality of glass was made was directed by Don Segismundo Brun, a native of Hanover, but who had been brought up from a very early age at La Granja. It was this artist who invented gilded glass a feu. A large number of foreign artists worked at this manufacture; they impressed their special style on the objects they made, which were similar to those of the same kind manufactured in France, England, and Germany.
From the time of Ventura Sit, towards the year 1734, the manufactory of glass at La Granja belonged to the crown, and continued under the protection of the Spanish kings, who spared no expense to obtain its development. Early in the present century this industry began to decay. Towards 1828 it passed into private hands, and continued to work until 1849. The manufactory is now closed, although there is some talk of reviving this industry.