Due to the fragility of unfired - at at times even fired - ceramics, the tusks here were carved from Gabonese ebony. Fired ceramic does have similar strength to marble, marble, alas, can also break. So you can really appreciate guys like Gian Lorenzo Bernini when he carved the leaves in his famous Apollo and Daphne. Of course, Bernini actually hired the young Guiliano Finelli to carve the leaves, twigs, and the other really hard stuff. That though was SOP for the time if you were a successful sculptor and even today the final stone sculptures are actually rendered by paid specialists hired by the actual artist. In any case, Guiliano became a successful sculptor in his own right and carved a bust of the hefty Cardinal Alessandro Peretti di Montaltoto. Naturally so did Bernini, and critics say Bernini's sculptor is better. Tough luck, Guiliano.
Bernin and the Excess of Art, Robert Peterson, Fordham University Press, (2003).