Steller's Sea Cow Bone

(via) Gemmology Queensland writes:

A rare ivory look-alike

Steller's sea cow (hydrodamalis gigas) is an extinct ancestor of the dugong that did not survive the 18th century. The first Steller's sea cows were discovered by Danish Captain Vitus Bering who was commisioned by Tsar Peter I (Peter the Great) to determine whether or not Asia and the Americas were one or two separate continents. One a second expedition in 1741, to map the area between Asia and North America, Bering was accompanied by a German doctor-naturalist named Georg Wilhem Steller. During this expedition, the ship ran aground and before his colleagues escaped, by building a new boat out of the timbers of the wrecked vessel. Steller, who died on what is now known as Bering Island, catalogued numerous species of plants and animals, some of which are named after him.

One such marine animal was a large sea cow that is now known as Steller's sea cow. This herbiverous marine mammal was twice the size of the presently living dugong. It had a length of 8.5m, a girth of 6.7m, and weighed up to 3628kg (8000 pounds0. It had no teeth, but its bones were massive. At the time of their discovery it is likely that from 1500-2000 Steller's sea cow were in existence. Due to the delicacy of their meat, by 1768 the last sea cow had been killed, with Stellar dying only four years after the expedition, never knowing of the extinction of the animal that bore his name.

Since the 1800s, there have been reported sightings of small colonies of Steller's sea cows in remote areas away from Russian fishing grounds and boat traffic. The few intact skeletons of Steller's sea cow that still exist can be found in a few museums that are scattered around the world. Today, the skeletal remains of this now extinct sea cow are recovered by indegenous natives from both sides of the Bering Strait, and these bones are either being sold as rough or are carved into some attractive ivory-like objects, such as knife handles--usually after they have been impregnated with a colorless synthetic polymer. The raw material, which seems to be predominantly derived from the large ribs of this now extinct animal, has a grayish to brownish color, is relatively porous, and has a core of or porous cacellous bone and an outer layer of thick cortical bone. This is rare, but very interesting material that could be misidentified as ivory.