This experiment is very easy to do but will blow your mind. We have said time and time again that light can bend and reflect in crazy ways. Here is another example of that.
Just by charring the outside of a raw (or cooked) egg shell and dipping it in water, you will be able to see something crazy! The egg appears to turn silver. But when you lift it up out of the water again it goes back to black?
The carbon soot that builds up in the outside of the egg is a combination of multiple sized particles of carbon. Those particles trap air along the surface.
This air layer traps light that is traveling through the glass, water, and air, and causes total internal reflection to occur. Total internal reflection is when light enters a medium and is reflected back and forth at the boundary of the medium, in this case the water and air boundary.