jacob1:
I think it's a glitch. Just change it's color before you draw it and it will appear the color you want it to.
to change particle color:
Press "B" to open color menu and then choose a color then when your done
use it on a particle.
Ex:
Particle= Powder
Color=Red
while in color mode, click and drag on the particles and it will turn into color red.
A 10 month necro. Nice.