Stained Glass

We're Alettie and Yvonne! We live in Chicago and recently we decided to go to the MSI (that's Museum of Science and Industry) for its 75th anniversary. While we were there we met Annette and G. Brian, glass artists from the Corning Museum of Glass who made a glass dragonfly for us from our very own design! We also spoke to a stained glass artist, Erin Botti, who told us that the colors in stained glass come from metals like gold and silver. Our question: How can gold look red and silver look yellow?

What did we do?
We went to visit Mark, a graduate student at Northwestern University. Mark helped us mix different chemicals together with gold and silver to make them nanosized and they turned yellow, red, purple and even orange! Then, Mark used his SEM (Scanning Electron Microscope) to take pictures of the particles in each of the solutions that we mixed. Mark had us measure the nanogold and nanosilver to determine the size for each color.

What did we find out?
We discovered that stained glass gets its color from metals like gold and silver. Even back in the Middle Ages, people were experimenting with nanoparticles of metals to get lots of different colors. We learned that the size of the nanogold and nanosilver caused it to behave differently with light and create the beautiful colors we see!

What can you do?

• Grab a glass of water in a clear cup. Try shining a bright light (like a laser pointer) through it. Now add a splash of milk and try shining the light through again. What's different? The nanoparticles of metals in stained glass behave in a similar way to the milk!
   
  
• Take 3 strips of newspaper and place them inside 3 sandwich bags. Leave one alone. Put regular sunblock on the second (the kind that leaves big white streaks). Put sunblock with nanoparticles (it goes on clear) on the third. Make sure the sunblock is the same SPF! Place the bags in the bright sun for several days. Which newspaper yellows first? Does it matter if the sunblock is clear or white?
   
  
• Hunt for stained glass windows in your town. Keep your eyes open the next time you are in a store, museum or old house. Can you guess which metals give the stained glass those colors?
   
  
• You can make edible glass at home, but you may need an adult to help. Butter a cookie sheet and place it in the refrigerator. Put 1 cup of sugar in a frying pan and turn the burner on low heat. Stir slowly as it heats. Keep stirring when it gets clumpy. Eventually, it will turn into a thick brown liquid. Pour this onto the cold cookie sheet. Add food color for a stained glass treat!
   
  

	SciLinks Changes of properties in matter Go to the DFTV Boards, and tell us about your science investigation.