Preservation/Sealing of extremely fragile Green River Limestone

[Superhedger]

Hello,

 

My wife and I recently returned from the Green River Formation in SW Wyoming and have about 20 decent fish fossils.  The limestone was wet from snow melt and is currently drying out on a table.  My question is, what is the best medium to use to seal them forever?  I have read about using Elmers-Glue All, Butvar and other resins, and clear lacquer.  I read through some posts on this but they seemed more focused on cleaning/detailing the fossils which I have done as much as I am willing to risk already with an air blower and dental pick.  Once they are dry, what is the best method to seal them completely with a clear finish so I can give some as gifts and not worry about how fragile they are?

[Tidgy's Dad]

Nice haul. 

[Fossildude19]

@Ptychodus04  Should be able to give you some advice here.

 

It's a shame that about 3-4 of these could use more prep work. 

That Mioplosus' mouth is still covered over. Looks like a great fossil.

Welcome to the Forum. 

[Ptychodus04]

Generally speaking, Green River matrix is pretty stable once it is dry. If your pieces are starting to delaminate, you can drop cyanoacrylate into the cracks on the side to hold them together. Do not use Elmer’s glue or lacquer to coat them as these compounds will yellow over time and break down. If the fish are flaky, apply a solution of Butvar B76 or Paraloid B72 to them. It is stable indefinitely. Dissolve 1 part plastic into 50 parts acetone and apply with a small brush.

[Superhedger]

Thank you very much for all in the information.  This is my first time preparing them, but have worked with epoxy, resins, lacquers in my work before and have ordered Butvar and will let them dry out first until June 10th.  I will post them one by one for the ones I cannot identify in another thread.  My wife had a great time and we will definately be making another trip to the area from Jackson!

[Superhedger]

On 5/30/2023 at 4:41 AM, Fossildude19 said:

@Ptychodus04  Should be able to give you some advice here.

 

It's a shame that about 3-4 of these could use more prep work. 

That Mioplosus' mouth is still covered over. Looks like a great fossil.

Welcome to the Forum. 

Which four would you recommend I work on more?  Even my dental pick was disturbing some of the finer features, but perhaps dryer they will tend to clump and flake less.  This stone was quite wet when we split it.

[Superhedger]

On 5/30/2023 at 3:58 AM, Tidgy's Dad said:

Nice haul. 

Thanks man, I have found some minor shells sticks etc in shale but never anything like this!

[Fossildude19]

3 hours ago, Superhedger said:

Which four would you recommend I work on more?  Even my dental pick was disturbing some of the finer features, but perhaps dryer they will tend to clump and flake less.  This stone was quite wet when we split it.

 

 

[Ptychodus04]

3-4, or 7... 

[Superhedger]

My first experiment, I think the bubbles are from using to much Butvar in my solution, will go lighter for the next one.