NOC-Out Cover-Up Compact is the best concealer I've ever used. Though there are, in fact, three different cover-ups within the compact, based on the highly practical assumption that not all blemishes are equal. Red Guard is for neutralizing thread veins, rosacea or an angry flush; Spot Cover deals with your average zit, freckles and age spots; Eye Disguise conceals dark circles. Amongst the handful of vitamins in each, there is a potent and stable form of vitamin C called tetrahexyldecyl ascorbate and vitamin K1 (good for age spots and dark circles).
There is also a posy of botanicals: mushroom and licorice extracts, as well as impatiens capensis (jewelweed) for treating wounds and skin infections.
Read TIA's full review and the full list of ingredients and leave a comment on the post to persuade us that you are deserving and honorable (by which, when you say you'll write back with a review, you'll follow through).