I would describe the top left color as a plummy, dark brown, the top right as a slightly shimmery pale shell pink, the bottom left as a light pewter shimmer and the bottom right as a medium bronze with a taupe cast, which is also shimmery. They all have a shimmer/sheen to them, of some degree.
What I think is so brilliant about this quad, is that all the colors work so well together to create a very cohesive and polished look. You don't have to work for the palette, rather it works for you. The formula is soft, as Chanel's always are, but not overly soft as to increase the rate/potential of fallout or to apply overly sheer. I find the textures and level of pigmentation to work very well. I created this "look" in a very quick and sloppy manner. I was getting rushed out of the house, so all I did was slap the lighter brown color all over the lid and past the crease and then applied the darkest brown shade in the crease and the outer corner. I also took some of the dark brown on the pointy sponge-tip applicator that comes with the quad and applied some to the outer bottom lash line. I took a little bit of the pale pink shade and swept it on the inner corner of the eye to brighten up the natural shadow that falls there. Super quick, super easy, and absolutely foolproof.
I feel as though I can confidently say that the Mystic Eyes quad would work on anyone, at any age, and on any/most skin tones. Even those that say brown colors wash/dull them out or make their eyes look "dirty" shouldn't have a problem with that, because these colors are all a perfect balance of warm and cool tones, almost falling neutral. It's almost as though the actual pigment is cool toned and the shimmer warms it up. That's as best as I think I can describe the effect. Either way, I'm a big fan and perhaps a reformed Chanel quad hater.