Cathedral glass is a type of glass that is often used in windows of really big buildings like churches or cathedrals. When you look at it, it might remind you of a colorful rainbow!
But how is cathedral glass made? Well, first glassmakers start by melting different colored pieces of glass together. They melt the glass until it becomes liquid and then mix the colors together so that it forms a pattern. Then they take the liquid glass and shape it into a flat sheet that can be used in windows.
One really cool thing about cathedral glass is that it's made of many different colors instead of just one like regular see-through glass windows. This helps to create beautiful patterns and pictures when sunlight shines through it.
So, when you visit a big church or cathedral, look at the windows and you might see some colorful patterns made with cathedral glass!