A very similar glass table top by Giovanni Rossignani was sold in these Rooms, 6 June 1991, lot 300. One of the two other glass table tops of this type known was sold at Christie's South Kensington, 11 June 1987, lot 123. The other is in the Vatican, Rome.
Giovanni Rossigani is recorded as one of the mastri working in the Reverenda Fabbrica di San Pietro.
The glass fragments used in such tables come from mosaic glass vessels, mostly bowls, dating from the late 1st century B.C. to the early 1st century A.D. These include fragments of millefiori, ribbon-glass, reticelli and glass imitating marbles such as giallo antico and verde antico. These fragments were excavated in the nineteenth century and heated in order to level and smooth them. Dealers in Antiquities often polished them and mounted them in cardboard strips with gilded edges.