Re: When colour fades where does it go?

Remember that what we see as "color" is actually caused by molecules which
absorb certain wavelengths of light and transmit others.  Over time,
these molecules can slowly degrade; the products of that degradation are
colorless or white.  A prime example is the familiar old blue jeans.
The dark blue dye that is used to color them breaks down over time,
especially with exposure to the elements.  As more and more molecules
fall apart, the color gets lighter and lighter.  If the jeans held 
together long enough, they would eventually turn completely white.

So color doesn't really go anywhere.  It just literally fades away.