Tonals and semi-tonals are all dyed in very small kettle dyed batches. There can and will be areas that dye lighter and darker in every skein- which is the beauty of hand dyed tonals. Some of these colorways are made by dyeing the whole skein in more than one color for added depth and interest. It is always recommended to buy enough for your project at the same time so they are "pot mates" that match up well and also to alternate between skeins while working a larger project.