Well, yes, shea butter can be good for dark circles under eyes for they can help to fade away the dark colors under your eyes. Anyway, you can have a try. But you also should know that this is a long term task, only do you use them in a long time, it can make a good job to your dark circles under your eyes. Also, dark circles are a sign of lack of sleep and even the stress. So having a good rest can be effective. Of course, you can take some measures to reduce them. For example, Vaseline which contains vitamin E and C are good, by using them, it will make your skin sticky, and in that way, it will also helpful in reducing the dark circles. Besides, lemon juice, olive oil can be good for your eyes, also, there are many other factors that can cause dark circles under eyes, such as the allergy and alcohol, or stress, lack of sleep. So just avoid them too.