The most famous modern practitioner of this medium used them in lampshades, and created the "favrile" variety through treatments of metal oxides.
Clara Driscoll led a team of women in creating a celebrated daffodil design in this medium. Four 210-foot-tall works of this kind extend to a cross in the ceiling in a building in Rio de Janeiro. The attempted murder of King Chilperic and his subsequent protection by the Bishop of Tournai are depicted in a series in this medium by Arnold Njimegen. Saints Cyril, Methodius, and Wenceslas all appear in a work of this type in Prague by Alphonse Mucha. William (*) Morris collaborated in this medium on a Worship of the Shepherds with Edward Burne-Jones, who also produced a Nativity series in this medium for Trinity Church in Boston. The most famous modern practitioner of this medium used them in lampshades, and created the "favrile" variety through treatments of metal oxides. For 10 points, name this medium revived by Louis Comfort Tiffany, which might be found in the windows of Gothic Cathedrals.
Clara Driscoll led a team of women in creating a celebrated daffodil design in this medium.
stained glass [prompt on "glass"; be generous, and prompt on "windows" too before "lampshades," since most of these clues are about stained-glass windows]