Your answer is....YELLOW! Since yellow is the opposite of blue on the color wheel, If there is too much blue or purple under your eyes, choose a yellow color corrector to almost magically neutralize the blue/purple tones. It really works!
Powder color correctors and concealers are a breeze to use and they stay where you put them. Love that! A few other tips to help you feel beautiful:
Here is a good article from Mayo Clinic discussing the possible causes of dark circles.
Remember, opposites attract - Just as a green color corrector can easily hide red tones in your skin, yellow will help blue and purple fade away.