You have joined an organization that works hard to make artists aware of the issue of lightfastness. No matter what your artistic goals may be, it is devastating to think that all or parts of your artwork could disappear. And that is a real danger when artwork is exposed to light, particularly the UV rays in sunlight. Certain pigments may fade, change hue, or even disappear completely. The least stable colors are hot pinks, purples, blues, reds and oranges, while browns, grays, and other neutrals generally remain unchanged. It will be worth your time to learn more about the lightfastness of the colored pencil products you use.