Oh I don't know if it's actually anything special...it just looks light purple when it's all clenched up and that's what I call it. It's actually kind of fleshy colored when erect, like silly putty. The small piece I got from MIKE on here was light green. So just a designation....You are more than welcome to have a piece as a gift if you'd like, as I just cut one.
I'm pretty sure it's super common...