"Mammoth Ivory tusk hand carved by Japanese master carver." (Wikipedia)

The craft use of any kind of ivory is potentially controversial.  We have covered at least one ivory-related project, before, about the use of antique ivory piano keys in scrimshaw, but generally we have steered clear of ivory (I imagine) because it’s such a sensitive and complex subject.   Personally, though I often admire the beauty of carved ivory, I have avoided owning or working with it for ethical reasons.  On the other hand, if a junk piano with antique ivory keys were to fall into my hands, I would have no problem salvaging and working with them.  Indeed, it would seem wasteful not to do so.

There are several alternative / substitute materials available to a person interested in working with ivory.  One of these is so-called “fossil” ivory, which is harvested from mammoth remains preserved in Siberian permafrost. Per a 2009 story in The New York Times, “[t]he tusks are more abundant than many people in the West realize. Encased in an upper layer of Siberia’s permafrost are the remains of an estimated 150 million mammoths that lived from 3,600 to 400,000 years ago.”

A 2010 report in the specialist journal Pachyderm describes the annual mammoth tusk harvest: “Every year, from mid-June, when the tundra melts, until mid-September, hundreds if not thousands of mostly local people scour the tundra in northern Siberia looking for mammoth tusks. All are Russians as foreigners cannot obtain a permit to collect tusks in the field. Some tusks are easily seen on the banks of rivers while others are detected on the flat lands.” Further, the report claims, “[i]n recent years, 60 tonnes of mammoth tusks have been exported annually from Russia, mostly to Hong Kong for carving in mainland China.”

Whatever the larger implications of the mammoth ivory trade may be, it has created a practical forensic problem for law enforcement. Buying mammoth ivory is, generally, legal, while buying elephant ivory, generally, is not. But when you’re a customs official staring at a crate full of tusks, how do you know which is which?

Cross sections of elephant (left) and mammoth tusks (right) with outer Schreger lines marked, showing characteristic angle difference.

For an agent “in the field,” the simplest and most useful test is based on natural grain lines in elephant and mammoth tusks called “Schreger lines.” Tusk cross sections can be scanned on the glass of a photocopier, and the angles between Schreger lines near the surface of the tusk measured with ruler, pen, and protractor:

When averages are used to represent the angles in the individual samples, a clear separation between extinct and extant proboscideans is observed. All the elephant samples had averages above 100 degrees, and all the extinct proboscideans had angle averages below 100 degrees.

Further, mammoth ivory sometimes displays characteristic staining in visible and ultraviolet spectra. The U.S. Fish and Wildlife Forensics Laboratory’s Ivory Identification Guide, linked below, has more details, and is a great resource in general for anyone who may be considering working with mammoth ivory.

Ivory Identification Guide – U.S. Fish and Wildlife Service Forensics Laboratory