A third nipple, to most people's surprise, looks astonishingly similar to an ordinary nipple. The best way to confirm the presence of an extra nipple is to compare it to an existing and confirmed nipple; usually those which reside on your chest are conventional and most convenient.
Note the characteristics which distinguish a nipple. Most have a round, nearly circular boundary, the areola. A nipple's color is distinct from that of the surrounding skin; usually it is significantly darker, but sometimes the difference is slight. The center of the nipple raises up from the surrounding skin, especially in cold or aroused conditions. The areola often contains small bumps, which aid in your confirmation.
To help you in your identification process, we have prepared a number of slides which demonstrate
what is and is not a third nipple. Pay close
attention to them; they will be your most helpful guid to identifying a
Triple-Nipple.