While wattles can be an indication, they are not a guarantee for determination of sex. I have personally had male guineas with wattles that were identical to the wattles that the females had. I have seen photos of confirmed guinea hens that others have owned that were very large and cupped just like the wattles I would expect to be found on guinea cocks.
My Coral Blue guinea males have much smaller wattles than I see on other varieties.
