One of my daughter's friend is about to get a proposal. A marriage proposal, thank you! The boyfriend showed my daughter a set of really beautiful diamond rings in various colors, clarity and sizes. Yes, diamonds do come in colors of pink, yellow, blue and green. I'm not sure if there are other colors but I have seen the ones I mentioned. I particularly like the very light mint-green diamond. It's quite stunning. I also like the pink one as it looks so dainty. I'm not sure which one my daughter chose. I guess, whatever it is, it would look fantastic on the her friend's ring finger.