Hi, i’m new and I was wondering if someone could help me out……

I have 4 tattoos, all of them are black. I have a tribal-type design on my left arm that is only about 4 months old. I recently added on to it and I am pretty sure it is done peeling/healing and it is darker than the rest of the tattoo. All of my other tattoos healed the exact same color and I treated this one the exact same way I treated the rest of them. I have added on to a tattoo before and didnt have this problem. I am sure that the reason is NOT because the rest has faded. The wierd part about this is that you would normally lose color when it peels, but this one did not lose any color. Does anyone know is there is some kind of new ink that they might have used? Or have any other reason as to why this happened?

Thanks