So what is stained glass?

You’ve seen it in the windows of churches and on really expensive lamps, but what is stained glass?

The process of creating stained glass hasn’t changed since Medieval times. The stained part of the name refers to the act of coloring clear glass with chemicals, such as silver, and firing it in a kiln so that the glass changes color permanently, in this case, yellow.

Today, you can avoid this process altogether by buying glasses in any color you need, already stained.

Once you have a clear idea of the design and look of your piece, you begin by cutting the different colored sheets of glass into the shapes you need, from circles to squares, using a glass cutter — a tiny diamond-tipped wheel that scours the glass so then you can crack it apart.

Once you have your glass cut, you paint an image onto each piece. The easiest way to do this is by placing the glass on top of a light box, with the image you want to paint on the glaass underneath it, so you can easily trace it.

Next, you place the painted glass pieces in a kiln, fired up to 1,250 degrees, so the paint adheres to the glass, like a polish.

“Once that paint is melted onto the glass, there’s no way of it fading or coming off like paint might,” said Joseph Cavalieri, who teaches workshops on stained glass at UrbanGlass in Fort Greene, and is the creator of the piece pictured.

Once that’s cooled, you wrap cooper foil around each piece of glass, place your puzzle together, and bond the pieces together using solder — a mix of tin and lead — and a soldering iron that melts the mixture onto the copper foil. In addition to melding the glass pieces together, soldering also results in red lines between the glass that gives the piece the three-dimensional look and character associated with stained glass.

“Without the metal separating each piece, it would just be paint on glass,” said Cavalieri. “It would just feel really flat.”

Now that you have your very own glass art, find a light box to display it in front of, or simply use a window, and let the light shine through.