The shine on the edge of the shark teeth

[Jerrychang]

I have some shark teeth fossils, and some of them have some special shines on the edge of the blade. It will change color when you look from different angles.

I'm curious why this happens?

But like this indo megalodon, it didn’t has that shine.

[Jesuslover340]

If I recall correctly, that optical reflection is called "chatoyancy". More often used with gemstones, but I've seen it used in reference towards sharks' teeth occasionally. 

Edited March 1, 2022 by Jesuslover340

[sharkdoctor]

In the Calvert region, that sheen generally develops as the enamel degrades. It is most common in teeth that have been exposed to the elements, wear and tear, or acid etching.

Edited March 1, 2022 by sharkdoctor

[digit]

Though I've never confirmed this, I believe the effect you are noticing (which I've also seen on a number of teeth) is seen along the border of the tooth enamel (enameloid) because the enamel from both sides of the tooth meet to form a solid (and very durable) enameled edge. Toward the middle of the tooth the enamel is thinner and surrounds the dentin that makes up the bulk of the blade.

 

 

Cheers.

 

-Ken

[Gareth_]

Your answer lies within this thread..... 
It's a fantastic way to tell if the blade has any restoration near the serrations, you can't fake that 

I call it iridescence, the definition of the word seems to fit well with what we see on the teeth.

I recently bought some Carcharodon hastalis teeth, I noticed the same effect on those teeth.

It seems like it's due to how the enamel was laid down to make the tooth, the direction of fibres near the serrations and the thickness of the crown near the edge, the mineralisation makes it visible.

 

 

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