Not sure of the weight but, I have a couple of 5 gal buckets of mammoth ivory, some walrus ivory collected in AK, and several pliocene whale/walrus teeth. I also buy old piano keys to add ivory and ebony to my craft materials for different projects.
Using fossils is a logical medium for me. I have over 5 tons of high-graded raw material from collecting over the last 40+ years.