Freckles are a natural part of sun exposure, I have not looked into why they appear as I dont have time at the moment, but I am sure it is connected to melanin, as it is colouration of your skin.
I have lots of freckles on my arms, from over the years, but a few new, larger ones since using MT2, but they are exactly the same light brown type, that I have always gotten, no black spots at all.