The Space Shuttle was an incredible innovation and was a pioneer in innovating new technology. One of the unique aspects of the shuttle was the tiles that were used to help dissipate heat when the shuttle returned to Earth.
These tiles were made of 99.9% silica glass and are 90% air by volume. The tiles are terrible heat conductors, which means that even after being heated up to be red hot, they can still be handled with human hands. Check out this amazing animated GIF below:
h/t Solar VPS