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Cutting fossils

Hi I have been asked to cut a fossilised lemon shark’s tooth in half
lengthways and make two pendants that will match together.

What is the best way to cut it so I get a serpentine curving line
down the centre. I thinking it would no too hard to cut with a
jewellers saw. Any ideas greatly appreciated. Richard

A Diamond bandsaw will do the job, a stained glass artists suppliers
will have them. Do you know anyone who does glass art who could do
this for you?

Nick Royall

Note From Ganoksin Staff:
Looking for aBenchtop Bandsaw tool for your jewelry projects? We recommend:

a diamond coated spiral saw blade with a fine cut in a jeweler’s saw
with extremely secure hold downs or alternatively, a reinforced cut
off wheel in a flexshaft or dremel running with lubrication and at an
appropriate speed (maybe around 14,500-16,000 RPM, not full on). I
think you’re going to have a bit of a problem though in that it has
a slight curve to the tooth on the side that doesn’t face out, and
you need the smallest kerf possible to rapidly cut through porous
calcium based material. Be sure you explain that you will attempt it
but the risks are clear - that it could crumble through no fault of
your own. Do point out any lines (indicating a crack under the
enamel) you see both with a naked eye and using a loupe. Take a photo
of it, blow it up to the degree possible while maintaining clarity
and circle any areas you think may be problematic before beginning
and provide the client with a copy. I would also get them to sign a
waiver stating the value of the tooth and that you are released from
liability when attempting to cut it into 2 parts as specified by (the
customer). I would also absolutely wear a particle mask at least
while doing the job should you decide its something you want to do.
If you aren’t an experienced lapidary, why not contract that part of
making the pendant out 'that way you can add a fee onto the
lapidaries cost as well as the design and fabrication fees you will
get for making the pieces as a matching set. .(I use matching
loosely- one for each person the two halves will go to taking into
consideration each individual’s size and how each wants to wear it:
as a pendant at 22 " and one at 30" or a broach and pendant, or any
combination using each potential half of the shark’s tooth. . rer

Stuller sells splitting disks.006" thick 7/8" diameter (Stock #
11-8196). They work fine for cutting most everything including cobalt
steel used in engraving. They are very fragile and a lot of care is
need. Also very sharp if (and when) you run over a finger. Just
touching them wrong can break them but they’re not all that
expensive. Around $30.00 approximate for 100. I’ve used them for
cutting opal and lapis, but mostly metals.


Fossil shark teeth are an extremely fragile phosphate material. Any
vibration will shatter the entire tooth.

Coating it in superglue and using a true running diamond blade with
coolant- might work on a great white size tooth. Acetone to take the
superglue off. A small tooth- no way.

My advice is to not ever touch the shiny material with- anything.

Having done museum fossil prep & lapidary- stone is nothing like
metal. Trying to use a jewelers saw will be a futile. Destruction of

Brontotheroocity Stone Cutting on Etsy

If you had a Taurus ring saw, that would do it quickly, as would a
Gryfon diamond bandsaw. But I doubt it would be worth getting one of
those things just for this project. You can, however, get a piece of
wire coated with diamond abrasive that you can mount in your
jeweler’s saw, which would be a bit slower but would do the job
eventually, especially if you could drip a little water or coolant
solution into the cut as you went.

Here’s a place that carries them:

Andrew Werby