Let's get acquainted now with the history of stained glass art. Let's start with technological issues. It is quite clear that the development of stained glass, just like mosaics, had to keep pace with the progress of glassmaking. However, in the mosaic requirements for glass were very modest. It was enough to have small pieces of multi-colored opaque glass of any shape, which were cracked with a hammer, as was done with natural stones, the artist received the cubes he needed for a set of paintings. People learned to cook colored glass in pieces of small size for a very long time, and glass mosaic was widely spread at the end of the old era of chronology.