Best way to remove the matrix off a shark tooth.

[Samtheman55]

Hi everyone,

 

I found this mako tooth awhile back and I’m looking for guidance on the best way to remove the matrix off the tooth.  What would you recommend?  I’ve been able to remove some with just water and my fingernail, but the rest seems to be much tougher.  Any suggestions would be great!

[Kane]

Do you have any air tools like scribes? Barring that, delicate work with a Dremel might work. 

[digit]

That looks like really nasty limestone type matrix which is probably adhered quite strongly to the tooth. Often the smooth enamel makes matrix harder to stick so you might be able to clean up that part. It's the root that is going to give you the most problems. I've softened up matrix on things like echinoderm tests before with acetic acid (distilled vinegar) but I'd think that might dull the enamel on the tooth. I believe @MarcoSr has had luck removing matrix from fossils by soaking them in hydrogen peroxide (often in a ultrasonic cleaner). Don't know how well it would work with a big tooth like this with what appears to be sticky matrix.

 

This doesn't look like a Florida tooth. Where did you find this one?

 

 

Cheers.

 

-Ken

[Samtheman55]

3 hours ago, Kane said:

Do you have any air tools like scribes? Barring that, delicate work with a Dremel might work. 

I do not.  I do have a dremel though.  What type of air tool would you recommend for cleaning?  I’d be nervous to damage the back of the tooth with the dremel.

[Samtheman55]

2 hours ago, digit said:

That looks like really nasty limestone type matrix which is probably adhered quite strongly to the tooth. Often the smooth enamel makes matrix harder to stick so you might be able to clean up that part. It's the root that is going to give you the most problems. I've softened up matrix on things like echinoderm tests before with acetic acid (distilled vinegar) but I'd think that might dull the enamel on the tooth. I believe @MarcoSr has had luck removing matrix from fossils by soaking them in hydrogen peroxide (often in a ultrasonic cleaner). Don't know how well it would work with a big tooth like this with what appears to be sticky matrix.

 

This doesn't look like a Florida tooth. Where did you find this one?

 

 

Cheers.

 

-Ken

Thanks Ken, it is mainly limestone.  I’ll try the hydrogen peroxide trick and see if I can weaken the matrix. I’ll use vinegar as a last resort because I’ve also read that it can lighten the enamel like you mentioned.  If not then I’ll try some type of air scribe that Kane recommended earlier.

 

Here’s photos of the tooth when it was found.  It was almost completely covered!  This was found in the Chipola/Jackson Bluff Formation in North Florida.

[Kane]

23 minutes ago, Samtheman55 said:

I do not.  I do have a dremel though.  What type of air tool would you recommend for cleaning?  I’d be nervous to damage the back of the tooth with the dremel.

Air tools are going to be a huge leg up in terms of cost, as that requires a compressor, which are not cheap (look at compressors with good CFM and at least 110 PSI). It will be easier with air tools, but a Dremel could do the job if you're careful and aren't going to set up a lab. If you envision a lot of prep work in your future, air tools will be a solid investment. If not, then spare the cost to do it with a Dremel or contact someone who does fossil prep. 

[digit]

29 minutes ago, Samtheman55 said:

This was found in the Chipola/Jackson Bluff Formation in North Florida.

Ah, a very unusual locality for Florida fossil shark teeth. It's a locality well known for a rich assemblage of fossil mollusks. You don't much hear about the shark teeth from there.

 

The other chemical means that might prove somewhat useful is to soak the tooth in a bowl with Calgon water softener. That has been used to loosen up matrix (though mainly clay-based matrix). If you can get something to slightly soften the matrix you might be able to get it to pop off the tooth blade. The root is going to be much more difficult to get clean.

 

 

Cheers.

 

-Ken

[MarcoSr]

3 hours ago, digit said:

That looks like really nasty limestone type matrix which is probably adhered quite strongly to the tooth. Often the smooth enamel makes matrix harder to stick so you might be able to clean up that part. It's the root that is going to give you the most problems. I've softened up matrix on things like echinoderm tests before with acetic acid (distilled vinegar) but I'd think that might dull the enamel on the tooth. I believe @MarcoSr has had luck removing matrix from fossils by soaking them in hydrogen peroxide (often in a ultrasonic cleaner). Don't know how well it would work with a big tooth like this with what appears to be sticky matri

 

-Ken

 

50 minutes ago, Samtheman55 said:

 I’ll try the hydrogen peroxide trick and see if I can weaken the matrix. I’ll use vinegar as a last resort because I’ve also read that it can lighten the enamel like you mentioned.  If not then I’ll try some type of air scribe that Kane recommended earlier.

 

 

Don't put a tooth with matrix like this in vinegar.  I had a beautiful, shinny, deep blue C. hastalis with matrix like your tooth that I put in vinegar.  I checked it after an hour or so and it looked fine and the matrix was bubbling (acid was working) so I left it overnight in the vinegar.  Big mistake.  The next morning the tooth was a very light, faded blue (not a nice color at all) and the tooth shine was totally gone.  The other bad news was that most of the matrix was still on the tooth.

 

Ultrasonic cleaners can sometimes clean matrix off a tooth by breaking the matrix up.  I wouldn't use an ultrasonic cleaner on a fragile tooth but your tooth looks pretty solid.  Walmart 3% Hydrogen Peroxide can break down some types of matrix.  If you get fizzing the Hydrogen Peroxide is working.  Plus 3% shouldn't bother the enamel on your tooth.  I have cleaned matrix off some teeth in my ultrasonic cleaner filled with Hydrogen Peroxide using multiple cleaning cycles.

 

Marco Sr.

 

[digit]

Thanks, Marco!

 

I knew you had some experience with chemicals and the use of ultrasonics. I picked up an inexpensive ($40) ultrasonic jewelry cleaner online but within a few days it started getting very noisy (buzzy) and made noise intermittently. The instructions said to keep the tank at least half full (which I did) or damage could occur to the unit. Either I killed this cleaner or it was of inferior quality. May have to spend a few more bucks to get a better one to vibrate some matrix off some STH specimens.

 

Hopefully, the OP will try some techniques and keep us in the loop as to what worked (or didn't) as a service to the next person with a nice shark tooth with sticky matrix.

 

 

Cheers.

 

-Ken

[MarcoSr]

7 hours ago, digit said:

Thanks, Marco!

 

I knew you had some experience with chemicals and the use of ultrasonics. I picked up an inexpensive ($40) ultrasonic jewelry cleaner online but within a few days it started getting very noisy (buzzy) and made noise intermittently. The instructions said to keep the tank at least half full (which I did) or damage could occur to the unit. Either I killed this cleaner or it was of inferior quality. May have to spend a few more bucks to get a better one to vibrate some matrix off some STH specimens.

 

Hopefully, the OP will try some techniques and keep us in the loop as to what worked (or didn't) as a service to the next person with a nice shark tooth with sticky matrix.

 

 

Cheers.

 

-Ken

 

The ultrasonic cleaners that I've bought don't last long so I can't recommend a good one.  That said, I usually get a year or two use out of them before they snarge out.  I currently have three.  I pretty much wash all my small fossils (except fragile ones) in my ultrasonic cleaners with at least water from 1 to 8 cycles depending on the fossil types (teeth, vertebrae, coprolites etc.).  You have to be careful with vertebrae especially shark and ray vertebrae as they tend to break apart fairly easily.  The rivers I collect in Virginia are tidal so I want to get rid of any salt.  The land sites I dig in Virginia are loaded with pyrite so I want to get rid of any sulfuric acid residue.  Also a lot of my fossils from matrix have clay and sand on/in them that I want to remove.

 

Marco Sr.

[Samtheman55]

Thanks everyone for the suggestions!  I’ll give it a shot and update the results.

[digit]

We'll appreciate hearing about your results (positive or negative).

 

 

Cheers.

 

-Ken

[Coco]

Hi,

 

Hydrogen peroxide is especially effective on clay sediments, I am not at all sure that it can function properly on limestone.

 

When I use an ultrasound tray for small amounts of small fossils, I place them in a plastic container with water and a drop of dish soap that I put in the tub filled with water, This makes it possible to use less product in the plastic recovery and it works as well as if the fossils were directly in the ultrasonic tank basket.

 

In terms of cleaning up dirty shark teeth like this, I use a knife or scalpel blade, but keep it almost parallel to the fossil. However, with this method we must be careful not to cut !

 

Coco