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Help with Ammonite ID


olorotitan

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Hi, I bought this ammonite at least 10 years ago and have completely forgot about it since then.  It is rough on one side and cut and polished along the mid-line of the shell revealing the interior.  I'm certain it is an ammonoid (vs a nautiloid) due to S shaped suture lines and outward curving septa.  What I can't figure out is genus and locality of this ammonite.  I think it's fair to say this is a mass produced ammonite from madagascar or morocco but I can't seem to find much on the marker currently to draw an association. 

 

I've attached some pics.. thanks for your help!

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d.jpg

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I've also noticed the presence of bumps along the inner spiral of the shell (yellow circles).  These are regularly spaced and seem to end near the umbilicus.  There are also smooth bumps of lower height running along the outer spiral (pale arrows).  These are not as pronounced as the dark yellow but still noticable. 

 

 

c2b.jpg

cb.jpg

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58 minutes ago, Aurelius said:

Sutures look simple, perhaps a goniatite?

the fossil is quite worn,  you dont have the contact between the walls of septa's and the outer shell, so it will be quite hard to tell what it is exactly, it could be a goniatite or even a worn ammonite. the deeper you go in the shell of an ammonoid the less complex the walls of the septa become.

 

 

If you don't have info on the location or age, I would keep the id at "Ammonoid"

 

 

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33 minutes ago, Manticocerasman said:

the fossil is quite worn,  you dont have the contact between the walls of septa's and the outer shell ...

 

Well the external sutures do line up with the internal septa, if that's what you were meaning.  I don't think the outside is polished, there are still 2 sets of bumps.  But you're right, I can't tell if this is an internal mold or the actual exterior of the shell.

 

 

Clipboard01.jpg

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10 hours ago, olorotitan said:

 

Well the external sutures do line up with the internal septa, if that's what you were meaning.  I don't think the outside is polished, there are still 2 sets of bumps.  But you're right, I can't tell if this is an internal mold or the actual exterior of the shell.

It's a cast of the interior. Sutures are completely hidden by the shell if it is present.  

 

I also think this may be a goniatite. The sutures are too simple and it isn't too badly worn.

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