There once was a time when our world was mostly earthtones of brown, yellow, and green. Red, purple, blue, or other more brilliant colors came in small points, in ripened berries or the like. It turns out to be surprisingly difficult to find dyes which retain their color for long; even green is not as easy as you might think, if you want it to stay green for years.
Each discovery of a new pigment or dye led to a frenzied rush to acquire it, often at great cost. Telling the story of how this happened over the centuries, is one way to tell the story of how human civilization grew and developed and cross-connected, in all its gaudy and sometimes ethically dubious glory. This book does a lot in a small volume.
It is also, you will not be surprised to hear, quite pretty to look at, and not only because reading it helps you to appreciate just how much went into those colors on the page in front of you.