After the excitement of playing with a pile of new art materials dies down, the important job of testing for light fastness must be done. It is a simple task, but takes a couple of months to yield a result. The test involves putting a mark of all the new materials onto a piece of paper. Cutting the paper so that the marks are cut in half, then placing one half behind glass, on a window sill or ledge exposed to the sun and the other half in a book or dark draw. After 2 – 3 months compare the two halves and don’t use any of the products that show signs of fading or color shift.
With the ink marks, a graded dilution with clean water will also show the permanence of thin washes.
Many manufacturers provide light-fastness and permanence ratings on their products, but, for the small effort involved, it is worthwhile checking for yourself.
Splashing Paint 
Great Idea,
I have never thought about doing that…makes lots of sense though.
😉
ivonne
Hi Ivonne,
I always try out new materials like this. The biggest problem is finding the piece of paper I put away out of the light – they always seem to migrate.
Cheers John
Thank you for the idea. I usually just rely on the manufacturer but you are right – this would take almost no time to do and could be very valuable.
Hi Linda,
It’s worth doing – some of the manufacturers are a bit optimistic with their ratings!
Cheers
John
yes, good advice….thanks for the reminder 😉
Hi Cynthia,
Thanks for your comment, glad you found the post helpful
Cheers
John
Another great idea. I’m so glad I stopped by. Thanks again!
Hi artimagica,
Glad you found the idea helpful. Thanks for commenting
John