Warthog tusk vs Walrus tusk /and more ...( very interesting article !! to READ to learn more about the distinctive materials and ways to recognize them) more info about different ivories : http://www.fws.gov/lab/ivory_natural.php#warthog
|| An extremely rare narwhal skull with double tusks. There are only about 10 other bones like this in the world. Narwhals are a rare arctic whale. It is challenging enough to see one with one tusk. It is almost an impossibility to actually catch one with two tusks. Biologists estimate that there are only 1 in every 1000 Narwhal who actually have a double tusk. They are uncertain of why this phenomenon exists. They are even more uncertain why these sword like tusks occur on the whale.
Warthog tusk vs Walrus tusk : A nice clear comparison of fossilized walrus tusk (left) and warthog tusk (right) In the fossilized walrus tusk cross section (L) there's a large core of secondary dentine at the center. The warthog tusk cross section (R) has only a slender line of similar material. Again, walrus tusk cross section are rounded or oval, warthog tusks are four sided, hippo tusks are 3 sided