Stained Glass Window

The colors in stained glass come from metals melted into the glass itself. Cobalt makes the deep blue, while copper can give red or green. Each piece is then set into grooved strips of lead called cames. The sun pours through an arched chapel window and spills its colors across a stone floor, a stained glass jigsaw puzzle that is mostly light. Medieval churches used windows like this to tell Bible stories to people who could not read.