To test how much common art materials fade, last August I made a whole lot of swatches on strips of cotton rag paper. Then I cut the strips in half. I put the left half of the strip in a dark, cool drawer. The other half sat facing the sun in a south window for almost eight months. I tried all sorts of media.
How do fountain pen inks survive light exposure? All of them became lighter in value.
Here's a range of popular pens subjected to the same treatment. The blue Pilot Precise faded away to a light gray. Bic Ultra Round Stic stayed a little darker. The black Sharpie permanent marker did OK, but the blue Sharpie completely lost its color.
If you think these results are bad, wait until you see the markers tomorrow.
