These are living pieces of art and variations will occur daily and over time. Because of the dynamic quality of each piece art there is no way to predict the length of time they will change color. What we do know is that in an indoor environment Moving Color Studios art has exceeding 10 years. However, because every application is different we offer a 1 year warranty on all workmanship of each piece of art and its ability to change color. Every piece of art is hand made. Chips, cracks, bubbles and irregularities are inherent and part of the beauty of each piece. Because this art is made upon ordering there are no returns. If you have additional questions please use our website or call us direct at (916) 337-6296.