Decoration of bone or ivory objects, such as whale's teeth and walrus tusks, with fanciful designs, traditionally carved by Anglo-American and Native American whale fishermen with a jackknife or sail needle and emphasized with black pigments (e.g., lampblack). Among the traditional subjects are whaling scenes, ships, naval battles, flower bouquets, Masonic emblems, coats of arms, and the Irish harp. The earliest surviving examples date from the late 17th century, but the craft reached its peak in 1830-50. It is still practiced by whalers in Siberia and Alaska