Hell Creek Dino bone prep question

[Browning]

Hello all. 👋 Looking for some advice. I have some hell creek fm dino bone I would like to clean up but it has spots of lichen and iron. I tested some hydrogen peroxide in a small area and it seemed to clean up the iron. My question is if it will react with the "bone" material.  Maybe soak it in HP or even Iron Out?  Been a while since I took chemistry so I'm not sure about the interactions. Also, what is the best way remove lichen? Thank you in advance. 

[Ptychodus04]

22 hours ago, Browning said:

Hello all. 👋 Looking for some advice. I have some hell creek fm dino bone I would like to clean up but it has spots of lichen and iron. I tested some hydrogen peroxide in a small area and it seemed to clean up the iron. My question is if it will react with the "bone" material.  Maybe soak it in HP or even Iron Out?  Been a while since I took chemistry so I'm not sure about the interactions. Also, what is the best way remove lichen? Thank you in advance. 

 

do you have any scrap bone that you can test on? If so, soak a bit in each and see what happens. Abrasive is the best for removing lichen IMHO. It's so thin, tool removal tends to get to the bone as well.

[Browning]

I tried that last night. Did an overnight soak in 3% HP with no visual results. 😒 It sure was reacting with something but not what I wanted. 

[Ptychodus04]

36 minutes ago, Browning said:

I tried that last night. Did an overnight soak in 3% HP with no visual results. 😒 It sure was reacting with something but not what I wanted. 

 

Try the iron out

[Browning]

Does iron out stain the bone or have any other negative effects? 

[svcgoat]

I had some lichen on an ammonite I had somebody prep for me I think they just used an abrasive to blast it off but I know ammonite is different physical material than bone.

[Browning]

Sounds like abrasion is the way to go. Thanks Everyone. 

[Browning]

This is what I'm trying to clean off. Suggestions?  Most of it is too thin for a scribe and it's too hard for a toothbrush. 

[hadrosauridae]

Looks like a candidate for micro-air abrasion.

[Alex S.]

I agree with the others. If that isn't something you have available I've had a lot of luck with steel wire brush pens it's a lot of work but significantly cheaper than air abrasion. It is also easier to bust through the bone in thin places though

[Browning]

I thought of that but I'm too scared of destroying the bone. I'm not sure what the hardness of the bone is. Maybe I'll test some samples and see what happens. 

[Ptychodus04]

That looks like iron oxide, or some such thing. It's likely going to be harder than the bone. This can be tough to remove and one often has to settle for good enough.

[jpc]

10 minutes ago, Ptychodus04 said:

That looks like iron oxide, or some such thing. It's likely going to be harder than the bone. This can be tough to remove and one often has to settle for good enough.

I agree, but I also think there is no such thing as too thin for an airscribe.  Depends of course on what airscribe you are using and if you have magnification.  

 

But good enough is a good way to go.  This stuff is indeed very painstaking to remove.  

[hadrosauridae]

21 minutes ago, jpc said:

I agree, but I also think there is no such thing as too thin for an airscribe.  Depends of course on what airscribe you are using and if you have magnification.  

 

But good enough is a good way to go.  This stuff is indeed very painstaking to remove.  

 

Depending entirely on what scribe you have available.  I don't think most private preppers have the extremely fine scribes, combined with good microscopes to work that last tiny layer.  Even if they do, there is still a good chance you will remove bone as well.  Iron really likes to hold onto bone from my experience, and is normally harder.  When I get to the last layer, I try to remove it, but if I see thin layer of bone coming off with it, I stop and call it done for tools.  Thats the stage I might start trying chemical removal.

[Browning]

I've been pounding away most of the pieces with a scalpel and water/tooth brush. It works but wow it takes a long time. A lot of it would be fine scribe work but again that will take a loooooong time. I'm to the point I'll do what I can then let it be. 

@hadrosauridae do u know what chemical will take the iron oxide off?  

[hadrosauridae]

10 hours ago, Browning said:

I've been pounding away most of the pieces with a scalpel and water/tooth brush. It works but wow it takes a long time. A lot of it would be fine scribe work but again that will take a loooooong time. I'm to the point I'll do what I can then let it be. 

@hadrosauridae do u know what chemical will take the iron oxide off?  

 

I have only researched it to this point, I havent tried anything yet.  Do a google search for chemical removal of iron from fossils.  There are a number of papers written on the topic.

[Browning]

I'm not seeing a lot that is easily available to the regular Joe.  In unrelated threads I see things like nitric acid and edta (chelating agents) being used but then I don't know the interaction with the bone.  I'll start with the Iron Out in a small sample and see what happens. And likely keep looking for research papers when I get time. I'll keep the thread updated. 

[Ptychodus04]

On 1/8/2024 at 10:52 AM, jpc said:

I agree, but I also think there is no such thing as too thin for an airscribe.  Depends of course on what airscribe you are using and if you have magnification.  

 

But good enough is a good way to go.  This stuff is indeed very painstaking to remove.  

 

100%. The right tools make all the difference. 

 

 

On 1/8/2024 at 11:19 AM, hadrosauridae said:

 

I don't think most private preppers have the extremely fine scribes, combined with good microscopes to work that last tiny layer. 

 

This is where the determination of "good enough" comes in. It's always better to leave matrix on a fossil than damage it to get it off.

[Browning]

So I tried the Iron Out... no luck.  It did react but I did not see any visible change.  It is possible it softened the iron but it still didn't want to come off.  I got a bit frustrated so I did another online search.  Came across this study if anyone is interested.

 

 https://www.tandfonline.com/doi/epdf/10.1080/02724634.2023.2282650?needAccess=true

 

Hope that helps someone out there.  I really want to try a few of the solutions they used, even if it is on a small sample again.  Very interesting read...to me at least. 

[hadrosauridae]

4 hours ago, Browning said:

So I tried the Iron Out... no luck.  It did react but I did not see any visible change.  It is possible it softened the iron but it still didn't want to come off.  I got a bit frustrated so I did another online search.  Came across this study if anyone is interested.

 

 https://www.tandfonline.com/doi/epdf/10.1080/02724634.2023.2282650?needAccess=true

 

Hope that helps someone out there.  I really want to try a few of the solutions they used, even if it is on a small sample again.  Very interesting read...to me at least. 

 

Good paper.  Carbonic acid treatment looks like to could be a cost effective and useful treatment for ironstone bond fossils.  I did a quick search and the only supplier I found was Fisher Scientific, but their product has a Ph of 5.7 which is quite a bit weaker than the 2.5 used in the paper's test.

[Browning]

Welp the HCl 35% ate right through my sample piece. Not sure of the PH but I assume it was pretty low. In about an hour it ate up about 50% of everything. Going to try carbonic acid next. 

[hadrosauridae]

acid prepping requires you to watch it non-stop if you are experimenting.  Most acid preps are for a couple minutes, followed by long soaks in fresh water to remove all acid, followed by mechanical prep, then repeating and adjusting as needed.  

[EphemeralMoose]

52 minutes ago, Browning said:

Welp the HCl 35% ate right through my sample piece. Not sure of the PH but I assume it was pretty low. In about an hour it ate up about 50% of everything. Going to try carbonic acid next. 

Well yes, 35% HCl will do that to many things.

Dilute the solution with some water, start at 19 parts water to 1 part HCl, and then move up as nneeded. Remember AAA insurance: Always Add Acid [to water]. Never add water to acid or you may get a runaway reaction.

[Browning]

Thank you Mr. Moose and hadrosauridae. I will try round 2 this weekend...at a much more diluted concentration. Maybe a little soak will soften it up enough for some physical prep work. 

[hadrosauridae]

20 hours ago, EphemeralMoose said:

Well yes, 35% HCl will do that to many things.

Dilute the solution with some water, start at 19 parts water to 1 part HCl, and then move up as nneeded. Remember AAA insurance: Always Add Acid [to water]. Never add water to acid or you may get a runaway reaction.

 

2 hours ago, Browning said:

Thank you Mr. Moose and hadrosauridae. I will try round 2 this weekend...at a much more diluted concentration. Maybe a little soak will soften it up enough for some physical prep work. 

 

Yes, diluting acid can be VERY dangerous.  slow, slow, slow!  And do it in a well ventilated location.

"There lies Tom all calm and placid.  He poured water into acid.  Mary's smarter and did what she oughter, she poured acid into water."