Cornuproetus Trilobite

[DatFossilBoy]

Hello all,

I have received today In the mailbox a magnificent Cornuproetus trilobite from Morocco,that I got for relatively cheap on an auction site.

I was wondering if anything would point to the fact that it is restaured,repaired,painted or god knows what.

It is really perfect compared to other specimens, maybe « too » perfect?

It has very long spines compared to my friends specimen (approx 3,5 cm from bottom of the trilobite to tip of the spine)

The trilobite itself is approximatively 4cm (if unrolled)

I have spotted something bizar on the front that I circled in red. 

Any comment would help.

Regards Thomas

Ps: Tell me if you need more pictures.

[Kane]

It looks legitimate to me. Their genal spines do grow pretty long in relation to their overall body. As far as restoration etc., is concerned, they sometimes apply something to darken the trilobite to make it "pop" in relation to the matrix and disguise imperfections. It's a nice bug, decently prepared, and one I would not hesitate to display.  

[DatFossilBoy]

Ok great news. 

Thank you so much. So you say that there is possibly some kind of dark material added to the trilobite to make it better?

Regards

7 minutes ago, Kane said:

It looks legitimate to me. Their genal spines do grow pretty long in relation to their overall body. As far as restoration etc., is concerned, they sometimes apply something to darken the trilobite to make it "pop" in relation to the matrix and disguise imperfections. It's a nice bug, decently prepared, and one I would not hesitate to display.  

 

[Kane]

Well, I'm certainly no expert, but I've had my share of Moroccan bugs that are jet black, and I've seen comparable species that are dark but with more hints of brown, yellowish-orange etc., which leads me to think they might "enhance" the trilobite by applying some kind of uniform colouring. 

 

Can someone else out there with more experience with Moroccan trilobites confirm that this is the case?

[DevonianDigger]

It does look as though it was coated. But so is mine! (It's pretty normal on Moroccan bugs)

 

[Kane]

Thanks, Jay.  

 

Yet another bug that will look good in my dining room. I'll be monitoring my mailbox.  

[DatFossilBoy]

Okay Thanks all.

So the Cornuproetus are not naturally that black color. Is it sure that it has been coated?Can you see any things on the picture that leads to that?

Thanks for your help. 

Kind regards

On 3/14/2018 at 3:33 PM, DevonianDigger said:

It does look as though it was coated. But so is mine! (It's pretty normal on Moroccan bugs)

 

On 3/14/2018 at 3:00 PM, Kane said:

Well, I'm certainly no expert, but I've had my share of Moroccan bugs that are jet black, and I've seen comparable species that are dark but with more hints of brown, yellowish-orange etc., which leads me to think they might "enhance" the trilobite by applying some kind of uniform colouring. 

 

Can someone else out there with more experience with Moroccan trilobites confirm that this is the case?

 

[DevonianDigger]

I’ll get back to you on that. First, can you take a close up of one of the eyes?

[DatFossilBoy]

9 hours ago, DevonianDigger said:

I’ll get back to you on that. First, can you take a close up of one of the eyes?

Yes.Here are some pictures of the eyes.

Can you tell anything?Tell me if you need more.

Regards

[ynot]

9 hours ago, DatFossilBoy said:

.Here are some pictures of the eyes.

Can you tell anything?Tell me if you need more.

Wrong angle in these pictures. 

Need a shot that shows all of the lenses.

[DatFossilBoy]

9 minutes ago, ynot said:

Wrong angle in these pictures. 

Need a shot that shows all of the lenses.

There are 3 photos.

Do you need more showing the hole trilobite?

[gigantoraptor]

Cornuproetus has holochroal eyes, which means they have lots of tiny lenses on their eyes. I guess they want to see those. @DatFossilBoy

[ynot]

2 hours ago, DatFossilBoy said:

There are 3 photos.

Do you need more showing the hole trilobite?

All three pictures are of the top side of the eyes. A well lite picture that shows the side of the eye is what is needed here.

 

Regards,

Tony

[DevonianDigger]

Yes please, straight on at the lens. I didn't notice it at first, but after looking at it more I didn't notice really any lenses visible which I thought was a little weird. I'd just like to see what's going on there. The piece certainly looks genuine, but those lens surfaces look way too smooth from the angles I've seen. More curious at this point than anything.

[piranha]

20 minutes ago, DevonianDigger said:

Yes please, straight on at the lens. I didn't notice it at first, but after looking at it more I didn't notice really any lenses visible which I thought was a little weird. I'd just like to see what's going on there. The piece certainly looks genuine, but those lens surfaces look way too smooth from the angles I've seen. More curious at this point than anything.

 

 

Most holochroal eyes do not show the eye lenses.  The holochroal lenses are either not preserved or typically obscured by a corneal membrane. 

These figures show Gerastos and the lenses of another typical holochroal eye from an illaenid trilobite.  The individual lenses measure ~100 μm!

 

 

Schoenemann, B. (2007)
Trilobite eyes and a new type of neural superposition eye in an ancient system.
Palaeontographica Abteilung A, 281:63-91

[DatFossilBoy]

Here are some pictures of the eyes.

1 hour ago, ynot said:

All three pictures are of the top side of the eyes. A well lite picture that shows the side of the eye is what is needed here.

 

Regards,

Tony

 

6 minutes ago, piranha said:

 

 

Most holochroal eyes do not show the eye lenses.  The holochroal lenses are either not preserved or typically obscured by a corneal membrane. 

These figures show Gerastos and the lenses of another typical holochroal eye from an illaenid trilobite.  The individual lenses measure ~100 μm!

 

 

Schoenemann, B. (2007)
Trilobite eyes and a new type of neural superposition eye in an ancient system.
Palaeontographica Abteilung A, 281:63-91

 

33 minutes ago, DevonianDigger said:

Yes please, straight on at the lens. I didn't notice it at first, but after looking at it more I didn't notice really any lenses visible which I thought was a little weird. I'd just like to see what's going on there. The piece certainly looks genuine, but those lens surfaces look way too smooth from the angles I've seen. More curious at this point than anything.

 

[DatFossilBoy]

I looked very closely at the eyes and they are completely smooth.Normal?

[indominus rex]

In my opinion the right eye looks different from the left eye. I think the eye on the right looks repaired.

[DevonianDigger]

They look fine to me, I can see enough of a vague texture there. I was more curious than anything.

[DevonianDigger]

I’m not really an expert on Moroccan prep techniques, but it does look as though there were some repairs done and that it was then “painted” over. I don’t know what they use exactly, but I know they use some type of dark coating to make them stand out more. Those chocolate brown spots on the cephalic margin are more in line with their natural color.

[DatFossilBoy]

1 hour ago, DevonianDigger said:

I’m not really an expert on Moroccan prep techniques, but it does look as though there were some repairs done and that it was then “painted” over. I don’t know what they use exactly, but I know they use some type of dark coating to make them stand out more. Those chocolate brown spots on the cephalic margin are more in line with their natural color.

Okay Thanks alot.

Can you maybe circle or tell me which parts of the trilobite you think are repaired or painted on.

Thank you for all your comments everyone, it really helps me out  

[piranha]

1 hour ago, DatFossilBoy said:

I looked very closely at the eyes and they are completely smooth.Normal?

 

 

Yes, as I posted above, that is the typical preservation.  The lenses are covered by a corneal membrane.  

[DatFossilBoy]

6 minutes ago, piranha said:

 

 

Yes, as I posted above, that is the typical preservation.  The lenses are covered by a corneal membrane.  

A corneal membrane. Very interesting,thanks alot. Have to write it down.  

And for the concerns of @DevonianDigger do you have any clue of if it is repaired, painted or something else and where?

Really appreciate all the help.

Regards

[piranha]

29 minutes ago, DatFossilBoy said:

...do you have any clue of if it is repaired, painted or something else and where?

 

From the dark photos it is difficult to be precise.  The trilobite is nicked up in places, the genal spine tips are suspect, and the axis may have some minor repair work or paint. 

Assuming a reasonable purchase price, overall it appears to be a decent representative example of the species.

 

 

50 minutes ago, DatFossilBoy said:

A corneal membrane. Very interesting,thanks alot. Have to write it down.  

 

text from Schoenemann 2007:

 

"All lenses together are covered by a thin pellucid membrane, the cornea (Fig. 2). This membrane grades laterally into the integument of the cephalon. The form of the lenses is generally hexagonal, but sometimes as a result of their arrangement on the visual surface they may have another form, and so they may be observed to be hexagonal, rhomboid or even square. In early forms of the holochroal eye the lenses may be even round (CLARKSON 1997)."

 

 

figure from:

 

Levi-Setti, Riccardo 2014.
The Trilobite Book. A Visual Journey. 
University of Chicago Press 273 pp.

[DevonianDigger]

Sorry, I was away from technology and unable to respond sooner, but not only did @piranha cover it, but he’s propbably one of the most knowledgeable trilobite people out there, so his input is gold on this one