Stonewashing a kizer

[Johnny brown]

So I just bought a kizer t1. I looooove the knife but I hate the finish on the handle scales. Very cheap looking and feeling imo. I have experience stonewashing but just wondering if it needs any prep work as far as the finish that came on the knife first. I've never stonewashed anything with a finish like this and was just wondering if I can just stonewash em just like they are or if I have to sand em down or something, is this a blasted finish on this knife? Do I need to sand it first or will it look alright if I just stonewash it on top of the finish that's already on it.