 On the other hand, the mirrors also conveyed the king's wealth and the efficiency of the French economy in a subtle way.Mirror glass was an expensive luxury product in the 17th century and could only be produced with great effort.The manufacture of the mirror surfaces was the first major order for the Manufacture royale de glaces de miroirs, a glass factory founded by Jean-Baptiste Colbert, the later Compagnie de Saint-Gobain, with which the Venetian monopoly on the manufacture of mirrors in Europe was broken.