purposefully lightening tattoos

I have a tattoo on my lower calf, roughly 4 x 5 all black ink. It gets a lot of sunlight, and i am pale skinned, so its already fading to a blueish black despite the fact that its only 3 years old. what id like to know is whether or not it is possible to purposefully lighten certain areas of black to make them gray or blue, so that when i get a touch-up done i can add a little more texture to solid black areas. i considered the idea of white ink, but from what ive heard it only works on some people, and ive never heard stories of it being used over old black ink. any input or personal experience would be helpful.

Shooting white ink with the intention of purposefully lightening your tattoo is kinda movement without accomplishment. If there are areas of your tattoo that you feel are begining to fade (which is what it sounds like is going on) then really all you need to do is contact the artist who did the work and see about schedualing a touch up. Hope that helps in soe way. Take care....J