Yes I have. I use mostly concrete powdered pigments, but also use chalk line chalk. Some very nice work can be done on the rough side of buckskin, or braintanned buckskin, if you have deep pockets, by simply cutting the bristle on a paintbrush really short so they are stiff. Dry pigment is worked into the knap of the leather with a circular motion, a little at a time. Rawhide, buffalo skulls, bone, and tanned buckskin, can be painted with a combination of the dry pigment, artists acrylic flat clear, and water. Depending on the mixture the “paint” can be a light clear color, or a very opaque.
I painted a tanned buffalo hide some years ago that turned of wonderful. I used a piece of antler like the natives did, and worked it more like a stamp than a paint brush.
Hungry Horse