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Fossil ivory comes from three sources—it is either walrus ivory that has been
buried for hundreds to thousands of years or it is 10,000-plus-year-old ivory from the long extinct woolly mammoth or mastodon.
All of these ivories have been buried for centuries and have absorbed minerals from the soil that have turned them varying
colors from tan, orange, golden brown, and chocolate brown to even black; occasionally a blue or green color is also seen.
This ivory is not truly fossilized in the sense that the ivory has been replaced with minerals/stone; it is really just beginning
to become mineralized. It is in the earliest stages of fossilization and is just slightly harder than fresh ivory. "Fossil"
ivory can be cut or worked with the same tools that regular ivory is worked, the only difference you may notice is that due
to the minerals it generally has a rather unpleasant smell when it is being sawn or sanded and it takes an even better shine
than fresh ivory. The Ivory can be cut with any tool that will cut wood: a hack saw with coarse teeth,
jewelers saw (for very fine work), or better yet if much cutting or any slabbing is to be done, a band saw. Metal cutting
blades 1/2" wide with 6 to 10 teeth per inch seem to work the best. The fewer teeth per inch the less clogging with dust,
but the more teeth per inch the smoother the cut and the less subsequent sanding required. With any saw, a sharp blade is
essential as a dull blade will result in rough wandering cuts at best and scorched ivory at worst. The same goes for drill
bits, burrs and sandpaper: the easier it cuts the cooler it cuts! If you cut a tusk into sections or chunks you should seal
the pores on the cut ends to prevent rapid drying out and cracking. We have found smearing a white glue (such as Elmers) on
the cut ends to be the most convenient method and we have never had a piece crack that was so protected. Getting a mirror
smooth finish by hand can take practice; try rubbing with Simichrome metal polish or auto polishing compound on a rag. The
best results come from a fast spinning buffing or polishing wheel. We prefer an unsewn 54 ply 6" muslin wheel with a small
reinforced hole for use on a tapered spindle. The polishing compounds come in a waxy block or stick form and are impregnated
with fine abrasives. By holding the bar against the spinning wheel you will "charge up" the wheel with abrasive. Use tripoli
or bobbing compound first to remove any fine sanding scratches and to get a nice shine. Don't hold the piece in one spot or
press it hard into the wheel; this will nearly guarantee the development of the tiny cracks referred to as crazing (it may
take weeks or even months for them to show up). Then with a different buffing wheel use chromium oxide, Zam, Fabuluster, or
white rouge to put the glassy sheen on the ivory.
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