Moroccan trilobite cleaning query

[Aurelius]

I obtained a rather attractive triobite today (my first one) but knowing that these fossils are often tampered with to some degree or another, I decided to put a little acetone on it to see if I could expose any restoration or remove any coatings that may have been applied (I want it for macro photography purposes, and coatings would ruin that).

 

I covered it in acetone, left it for a few minutes, then rinsed it off. Now, instead of being jet black like it was originally, it looks silvery grey - like this:

 

 

Of all the things I expected, it turning grey wasn't one of them. I thought black or brown were the natural colours.

 

I don't really think the whole trilobite can be a fake, because for one thing it's too flawed, and for another the eyes have the tiny, tiny lenses. Have I just impacted upon a coating without removing it, or what? Any suggestions welcome!

 

[Aurelius]

Investigation with a sharp craft knife reveals that this white coating can be gently scraped off, but that's a task that would take many hours under close magnification. Can anyone offer any recommendations for chemically removing it? It's spent about ten minutes with a light coating of acetone on it so far, so perhaps longer exposure would break it down? Thanks.

[RJB]

Boy, thats a tuff one!  if you had several of them you could do some experimenting.   My guess would be to take some bicarb to it and see what happens?  

 

RB

[PaleoRon]

Unfortunately, a lot of the trilobites from Morocco are completely fake or composites. I have even seen fake trilobites with real eyes. The eyes can be hard to reproduce and the average Moroccan preparator is not working in a state-of-the-art lab. Even many of the authentic trilobites from Morocco are painted to make them stand out against similar colored matrix. It is probable that you have stripped off a layer of paint. Various man made products will present a white glaze when exposed to solvents. If the trilobite is epoxy, or has been repaired with epoxy, it will take quite a bit more time in acetone to see it begin to dissolve.

[Aurelius]

Thanks for the replies. I am now confident that it's totally genuine, but the thick layer of paint was there to disguise poor prep work. I managed to get most of it off by covering it in acetone for about an hour and a half, some detail work with a pin, and some elbow grease with a nailbrush.

 

Here's the 'before' photo:

 

 

And after, you can see the pen marks, bits of matrix not properly removed etc etc. I could probably clean it up a bit, possibly with abrasion but I'll have to look into that.

 

[Wrangellian]

Looks like you did a pretty good job of removing the coating.

It makes me hesitate to buy any Moroccan trilobites in future, though, knowing that it's so hard to tell what is real vs. what has been altered. I used to see trilos like these with 3-digit pricetags on them at rock shows. I hate to think people paid that much for them if they were poorly prepped and then disguised.

I suppose I have seen enough of these by now to be able to tell more or less, at least in hand or from good photos.

[Malcolmt]

Definitely looks real. You can see where the rock was originally split through the cross section of the trilo. Definitely think it was painted to cover a low end prep job.

[Aurelius]

Yes, it does seem like a minefield and makes me very wary of buying from unknown sellers. That being said, I purchased this from a dealer I've been buying from for a while, and it was only £15 ($19 US) which I consider a great price, even with the damage and the paint.

[aplomado]

Hmm, I guess that is why they always tell us to apply chemicals to a small part of the object first... yikes!

[Aurelius]

That wouldn't have helped if only a small part of the fossil had been restored, though - and it turned out fine

[RJB]

  Wow!  What a difference!  Nice job.

 

RB

[wamorris1999]

It looks great-

[aeon.rocks]

The white thing is probably glue or coating (even if glued only in one spot, one could easily get a white mess allover if trilo is soaked in acetone), which you could remove with a blaster or as you managed - with more acetone and a brush. Indeed the layer of paint/restoration and coating was there to disguise quick prep work and cracks, but to be honest, although it`s a poor prep job - it would be naive to expect anything else or a better prep work for 19$! They do it quick, so they can sell cheap, not many collectors willing to pay more money for a more detailed preped specimen... Besides, Moroccans are selling unprepped crotalocephalinas for 15-40$! Costs about the same as quickly prepped moroccan bugs...  So there are not many preparators crazy enough to invest dozzens of hours into a detailed preped specimen and then sell it for 19$. None that I know, at least; it`s a simple question about how much is your time worth... Could easily take between 10-30 hours to prep a nice detailed nice crotalocephalina, do the math! It even doesn`t look so badly prepped (especially considering the costs), these are often sticky and problematic to clean...

[LordTrilobite]

On 8/27/2017 at 2:01 AM, Aurelius said:

That definitely looks real.

 

Btw, if you want to hide those ugly prep marks and breakages. The white colouration is because there is air in those breakages. If you use a grey marker pen (not black, that's too dark), the ink will seep into the cracks. You can wipe away the excess on the outside and the ink inside the crack will hide most of it, making the trilobite a lot more handsome.

[Aurelius]

4 hours ago, LordTrilobite said:

That definitely looks real.

 

Btw, if you want to hide those ugly prep marks and breakages. The white colouration is because there is air in those breakages. If you use a grey marker pen (not black, that's too dark), the ink will seep into the cracks. You can wipe away the excess on the outside and the ink inside the crack will hide most of it, making the trilobite a lot more handsome.

 

Great tip, thanks! I need to replace my compressor, but once that's done I will blast it a little to remove the excess matrix, and then do as you suggest with a grey marker pen. 

[aeon.rocks]

And that`s not cheating just like moroccan paint job, except more limited? Kidding. Btw, you could aswell use a bit of carefull sandblasting to "hide" the hits and clean some more matrix between the pleural sements; should look much nicer.

[Aurelius]

On 10/12/2017 at 10:52 PM, aeon.rocks said:

The white thing is probably glue or coating (even if glued only in one spot, one could easily get a white mess allover if trilo is soaked in acetone), which you could remove with a blaster or as you managed - with more acetone and a brush. Indeed the layer of paint/restoration and coating was there to disguise quick prep work and cracks, but to be honest, although it`s a poor prep job - it would be naive to expect anything else or a better prep work for 19$! They do it quick, so they can sell cheap, not many collectors willing to pay more money for a more detailed preped specimen... Besides, Moroccans are selling unprepped crotalocephalinas for 15-40$! Costs about the same as quickly prepped moroccan bugs...  So there are not many preparators crazy enough to invest dozzens of hours into a detailed preped specimen and then sell it for 19$. None that I know, at least; it`s a simple question about how much is your time worth... Could easily take between 10-30 hours to prep a nice detailed nice crotalocephalina, do the math! It even doesn`t look so badly prepped (especially considering the costs), these are often sticky and problematic to clean...

 

I didn't expect it to be perfect, $19 is ridiculously cheap. I was hardly complaining.

[aeon.rocks]

On 10/14/2017 at 4:09 AM, Aurelius said:

 

I didn't expect it to be perfect, $19 is ridiculously cheap. I was hardly complaining.

 

My reply was meant in a more general nature. Not a lot of perfectly prepped and perfectly preserved 100% natural bugs around, that`s also the case for Russian trilobites, trilobites from USA or trilobites from EU, but a lot of people hesitate to buy Moroccan trilobites or think everything from Morocco is fake or are expecting visually good looking all natural perfect specimens of common species for 20$ and can`t justify 3-digit or 4-digit price tags on Moroccan trilobites.