How to prep coral colony?

[saidthegirl]

I would greatly appreciate any advice on how to clean/prep this coral colony. It was found in a shale pit in northern Iowa-from the Lime Creek formation. As you can see, there’s quite a bit still clinging to it. Is it safe to clean with some water and a toothbrush? The underside seems to have crystallized(?). Very new to fossil collecting and subsequent preparation. Thank you in advance!

 

If anyone has a guess at ID please let me know as well. 

 

 

[digit]

@Bev  @minnbuckeye

 

Any thoughts on cleaning up these colonial corals?

 

 

Cheers.

 

-Ken

[hadrosauridae]

Looks to be soil/clay on the surface of it, so I dont think you'll have any trouble starting out your prep with a toothbrush and water.  you could always start on an edge or corner to make sure you arent removing any detail.

[fossilhunter21]

Yep, I would try to use a toothbrush and water. But be VERY careful. It looks like it shouldn't be super fragile, but fossils can be fragile, even if they don't look like they are. It looks like it is just dried soil, so it should pretty easy. 

 

-Micah

[FossilNerd]

I agree with the others and think a little water and a toothbrush would go a long way here. I’d start with one of the soft bristle brushes with running water. I don’t know the matrix from the area so I can’t suggest soaking in water, but from the look of it I think a light scrubbing with a soft bristle brush under a running faucet should be fine.  

[minnbuckeye]

Nice find! Give it a good soap and water scrubbing. The corals in our area are tough and can handle physical hardships like that. It looks like it might be a colonial rugosa but is too dirty to tell for sure. Please post another picture after cleaning so further cleansing advice can be given if needed. Here is a picture of a colonial rugosa. Your specimen shows only the tops of the individual corals. The rest is filled with matrix.

Colonial rugose corals

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[Bev]

After you do the initial cleaning try vinegar, limeaway, a good toilet cleaner that attacks time, a splash of diluted hydrochloric acid and wash away immediately it it sits too long it will eat away at the coral but it can bring striking results!  :-D

[Kane]

If you want to do this piece justice, abrasion is the way to go if you have the means for it.

[Acb13adm]

Absolutely do NOT use acids or CLR type products! Fossils which have been formed by Silicification can withstand such, but corals originally formed of calcium. They and some other fossils can be eaten by these products. If it's just mud, and since coral can be intricate and delicate, I'd suggest just putting it under running water at first & see what comes of that. 

Remember, you can always clean again more aggressively, but if you start cleaning that way, you can't go back and fix it