Excellent in my CP Soap "Musk."
It's an attention getting color and my male customers love the look, too. Absolutely beautiful and easy to work with, as well.
I agree it's not activated charcoal black. However still blends very well. We like it a lot for making black swirls.
I also couldn't get black, like another in the reviews mentioned. However, I was able to get a rich dark chocolate color and I love it. So, this may be the clay if you are looking for brown, and I'd probably stick to activated charcoal for black. How I achieved the color: 16 ounces of oil, coconut oil (only) base, and 3 teaspoons of clay.
I never got a true black from this - just a muddy brown. Much better off with a black oxide.