What is a dye lot and why do they matter?

Here's another reason we call ourselves "detail oriented"...A "dye lot" is the number printed on the box of tile that specifies when that tile was made...It's a batch number. We picked up tile today that was a different dye lot. We put a stop to the project because we will not install tiles that are made at different times and have different dye lot numbers. Although the difference in the tile may be very small between dye lots, there IS a difference. We make it a rule of thumb to CHECK the dye lot number upon pick up and if they are not all the same, we don't install the tile. We're not going to take the chance in your $20,000+ master bath. Another noted benefit of using Hamilton Tile.