black sic P powder

Why is black sic P powder used when producing sponge sandpaper/sand blocks?

Why is black sic P powder used when producing sponge sandpaper/sand blocks?High hardness and wear resistance‌, Excellent thermal conductivity‌, Stable chemical properties‌, Good self-sharpening‌, Improve grinding efficiency‌, Improve processing quality‌, Extend service life‌