Please remember that these are living tiles and variations will occur daily and over time. Because of the dynamic quality of these glass tiles 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® has been witnessed as exceeding 7 years. However, because every application is different we offer a 1 year warranty on all workmanship of each tile, and its ability to change color. Every tile is hand made. Chips, cracks, bubbles and irregularities are inherent and part of the beauty of each tile. Because these tiles are made upon ordering there are no returns.