Removing coating from fossil fish

[Misha]

I have recently received this Palaeoniscus freieslebenensis from @Strepsodus, and it has some kind of coating around the fish, the matrix is slate and I would prefer to have it without this coating but I don't know if I can remove it, and even if can should I do so or would that risk the integrity of the fossil?

[Fossildude19]

Misha, 

Do you know what was used to coat it? And why? 

 

I suspect it was done to make the fish stand out more. 

It looks like a poor prep job that got overly abraded, to me. 

 

You could try a small bit of acetone, maybe near the end of the tail. 

The other option would be to use whatever was used prior, and fill in the body. 

 

This is what I suspect is the actual outline of the fish:

 

[Misha]

20 hours ago, Fossildude19 said:

Misha, 

Do you know what was used to coat it? And why? 

 

I suspect it was done to make the fish stand out more. 

It looks like a poor prep job that got overly abraded, to me. 

 

You could try a small bit of acetone, maybe near the end of the tail. 

The other option would be to use whatever was used prior, and fill in the body. 

 

This is what I suspect is the actual outline of the fish:

 

Hi Tim,

Thank you for the input, I am not sure about what was used to coat the fish, I will try the acetone when I get a chance.

As far as the prep it is hard to see with that coating, I think it was done with the purpose of making the fish look more complete than it is as it does follow the body of the fish but there are some patches where there are no scales, 

Also you are more knowledgeable on fish than I am, I think this may be the ventral side of the fish what do you think?

[Fossildude19]

That's a shame, as this fish has a pretty neat detail, I thinkl. 

It looks to me like the area missing scales has had it's scales folded over the front part of the body - see how it looks bunched up right before the void?

Also, the orientation of the scales is wrong for it's body pattern. 

 

Luckily, you can still see this, but I hate to cover over natural fossils. 

 

[Misha]

2 minutes ago, Fossildude19 said:

folded over the front part of the body

That's interesting, would this have happened in fossilization?

[Fossildude19]

More likely during pre-fossilization. Probably rotted, then the skin\scales came loose either from expulsion of decompositional  gasses, or came apart in a current, and settled back down over the fish. 

Pretty cool looking, if you ask me.  

 

[Misha]

3 minutes ago, Fossildude19 said:

More likely during pre-fossilization. Probably rotted, then the skin\scales came loose either from expulsion of decompositional  gasses, or came apart in a current, and settled back down over the fish. 

Pretty cool looking, if you ask me.  

 

That is very interesting, I hope I can get that coating off.

I think coating it may be a good idea in the future but with some other substance that would not impact the presentation as much.

Thank you for all the help.

[Misha]

I was successful in removing the mystery coat with acetone and I think the fish looks great even though it may not be complete, it even has a wonderful sheen to its scales. Now it's time to make a stand for this fossil.

I could not have done this without Tim's advice, 

Once again thank you very much!

Misha,

[Wrangellian]

Success! I think it looks even better without the coating. Certainly more natural. I wish people would not add artificial enhancements to fossils... it never looks right. I have had trouble finding those Ephemeropsis nymphs from China that haven't been similarly treated.

Just in answer to the general question, for any reader: My instinct would always be to try acetone first, for removing coatings. Maybe water first, in case it is water soluble (like hairspray, I understand, though it would not look like this), and only if the specimen doesn't look like it would fall apart upon getting wet. But I believe acetone will dissolve most things, and not harm the fossil, generally speaking.

 

Did you use a Q-tip or did it just rinse off on its own under an acetone wash?

[Misha]

On 12/14/2019 at 6:33 PM, Wrangellian said:

Did you use a Q-tip or did it just rinse off on its own under an acetone wash?

I tried using a Q-tip first but it was taking off little while the fibers were becoming lose very quickly, I switched to using cotton discs which were a lot more successful.

 

Also yes acetone is probably best for removing this kind of stuff, my primary concern was if it would stay together when I did remove the coating.

[RJB]

  Its great to see things happen on the forum.  Lots of guys who know their stuff. 

 

RB

[Fossildude19]

16 hours ago, Misha said:

I was successful in removing the mystery coat with acetone and I think the fish looks great even though it may not be complete, it even has a wonderful sheen to its scales. Now it's time to make a stand for this fossil.

I could not have done this without Tim's advice, 

Once again thank you very much!

Misha,

 

 

 

Misha, 

Glad it worked for you. 

It looks much better now.   

[Fossildude19]

18 hours ago, Misha said:

Also you are more knowledgeable on fish than I am, I think this may be the ventral side of the fish what do you think?

 

As far as how it was preserved - it is difficult to tell with the level of prep and poor quality of preservation, but I would be more inclined to think it was dorso-ventrally preserved.

(Flattened from the top to bottom.)  I cannot make out any gular plates (bones covering the underside of the mouth/throat).

That would indicate to me that it is the top of the skull showing. But, I could be wrong. As I stated, it's hard to tell for sure. There is really no definitive detail to the skull.

 

 

 

The lack of any pectoral, pelvic, or anal fins visible, also suggests dorso-ventral preservation.

[Wrangellian]

23 hours ago, Misha said:

I tried using a Q-tip first but it was taking off little while the fibers were becoming lose very quickly, I switched to using cotton disks which were a lot more successful.

 

Also yes acetone is probably best for removing this kind of stuff, my primary concern was if it would stay together when I did remove the coating.

cotton disks?

[caldigger]

7 minutes ago, Wrangellian said:

cotton disks?

Eric, they are the type for removing make-up.

[Misha]

25 minutes ago, Wrangellian said:

cotton disks?

Sorry I misspelled it , supposed to be disc

Just what I found nearby

[Wrangellian]

disk/disc, I don't care, but I had no idea what those were! (Thanks Doren.)