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Preperation On St. Mary Formation Bone Material


Mattalic

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So glad I joined the forum recently.

Years ago, I was an undergraduate in PA in Geology, and finished some other degrees in Climatology along the way. Although my academic geology days are gone, I collected a lot and visited areas along the east coast, including the now defunct Fruitville Quarry for the Kinzers formation - and finally did some field work in Montana (I will post another thread shortly about a fossil I found in Elk Basin that I would love some pointers on).

I found these bones in Maryland along the coast around 7 years ago. My notes are poor, but I believe them to be from the St. Marys formation (?) though please correct me if I am wrong here. My guess is from a field trip to Calvert Cliffs, or the area where the Mary's may outcrop. The matrix is a grey, very dense, putty/cement like clay that I remember sticking to everything. Over the years, it has dried forming a tough cement.

I believe these are Whale.

I would love some pointers on what you think I should do, if anything, to preserve and better display these pieces. I dread the idea of them slowly drying out and turning into dust. I have a few more small bones (finger bone maybe?) from the same location, one of which is a gorgeous brown tone. You can see the tone coming through a little bit on the larger rib bone but the clay material covers it up a bit - and fills some cracks along the side. The bones are very heavy.

Should I work this with a toothbrush, an air abbrasive unit, a scribe.... and butvar-76 it? Any thoughts, comments, suggestions would be greatly appreciated. I have never done any prep. and have some great rough laying around with parts of trilobites, bones and other bits and bobs that would be great to work on!

Note: I know the rib is rotated - I didn't want it convex-up as I would think it would stress it.

post-15846-0-05200000-1405100640_thumb.jpg - I don't know how to add photos efficiently to the forums yet... so I will add more images in reply posts.

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Adding photos - close-ups.

post-15846-0-15813300-1405100863_thumb.jpg

The clay has gone into some of the cracks, pulling in some fossil shell fragments. Some of the shells in this formation were gorgeous... very fragile but the detail was tremendous. I will gladly post a few images of them if there are any shell lovers.

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More close-ups for better views:

post-15846-0-31078900-1405100910_thumb.jpg

You can see the brown tone pushing through the thin layer of cemented, high-density clay.

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Final one - again sorry moderator, as I don't know how to add more than one high-res. image.

post-15846-0-56279500-1405100945_thumb.jpg

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Typically the bones from there are very well preserved and need no staibilzation. If you fear yours might have some weak areas I would recomend one of the butvar type materials. If you do a search for that term on this site you will find a wealth of information. For cleaning a tooth brush or even a popsicle skick usually works well for gently removing the matrix.

Also I believe your long section of "rib" could actually be a section of jaw from a baleen whale. We have a very knowlegable memeber on here that will chime in I'm sure.

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Ditto that. Longer section is a baleen whale jaw section (lower part?). Congrats!

As for prep a tooth pick or bamboo skewer lightly worked on the "grey" clay will scrape them free. I wouldn't worry too much about stabilizing. The only part of the jaw that should be "fragile" is the exposed end but even that is stable in my experience so long as you aren't handling regularly. If really concerned do as Kevin suggests with the butvar material.

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St. Mary's and Calvert FM clay residue responds very well to a going-over with a wet toothbrush; just don't get the bone soaked so that is wets it deeply. Aside from unstable cracks, most bone from there is pretty solid, and don't need consolidation.

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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That's fantastic gents. Thanks so much! Ill use a damp soft toothbrush and see what I can uncover. There are some interesting features near the tip of the jaw bone - small dark flatten spheres.

Should I dig the clay out of some of the cracks or should I leave it there for stability (e.g. the second picture).

And I am very happy to learn that this is a jaw bone! Thanks again for the identification.

Here's an image of the other bones found on the same trip. I could have spent all day there.

post-15846-0-40840500-1405106152_thumb.jpg

Note the two smaller bone fragments color - the little one seems almost agatized up close with a nice sheen.

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Hi,

I will gladly post a few images of them if there are any shell lovers.

Here we are ! ;)

Coco

----------------------
OUTIL POUR MESURER VOS FOSSILES : ici

Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici
Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici
Mâchoires sélaciennes récentes : ici
Hétérodontiques et sélaciens : ici
Oeufs sélaciens récents : ici
Otolithes de poissons récents ! ici

Un Greg...

Badges-IPFOTH.jpg.f4a8635cda47a3cc506743a8aabce700.jpg Badges-MOTM.jpg.461001e1a9db5dc29ca1c07a041a1a86.jpg

 

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Congratulations on the nice whale piece. My guess is it will clean up with ease using the recommended techniques. If it were mine I would leave the clay in any fissures and just try for a clean, attractive surface for display. Once the clay is gone a light rub with an art gum eraser may provide a "prettier" surface.

I am also taken by the pictured, spherical object with the reddish sutures, You don't see many unhatched dinosaur eggs!

Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See

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...I am also taken by the pictured, spherical object with the reddish sutures, You don't see many unhatched dinosaur eggs!

A DNA sample will reveal it to be a horse egg. ;)

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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A DNA sample will reveal it to be a horse egg. ;)

Aw, come on Auspex, don't be a neigh-sayer. There will be plenty of time to comment when that egg un-foals.

Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See

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You guys are fantastic.

I will get to work on this piece and post images as I go along.

I will dig up some of the shells I found on the trip COCO and post them here. Unfortunately an absolute beautiful one, a whole conch-like shell, pure white, wonderful twists and turns, broke on my last move. It was just so thin...

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Any pro tips on putting the two pieces of the jaw piece together? PVA + some of the gray clay? Butvar mixed thick? They fit perfectly together.

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If it's a good, tight fit, I like cyanoacrylate gel.

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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If you plan on using any type of PVA to consolidate and glue with acetone as a solvent perform the consolidation first

then glue or the solvent will soften the glue and you will have problems. I know this from experience and it was not

pretty!

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I was going to go with the suggested butvar material on the bones.

Any tips on preparing this specific piece with butvar given how long it is? Dont want to have to mix a whole bucket up just for these two pieces - would a baster work to coat it a few times to let it soak through?

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Yes, you want to drip it in very slowly so it can soak up the butvar as deeply as possible. After you do a coat of butvar, if you wanted to add more, the acetone would have to dissolve the first layer of butvar before it could go any deeper. So instead, drip slowly and let it absorb as much as possible in one sitting. And be careful - the acetone might weaken and soften the bone, so try not to move it until it's dry. Luckily your bone looks fairly sturdy.

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How does one avoid messing up the portion of the bone that will need to be resting on something - won't there be a contact point?

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I have used a board with a few nails driven through so that the fossil sits on the very points of the nails. There won't be enough contact to glue the fossil to the nails but will keep it suspended.

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I'd try to avoid the support/contact area, and get the top side well consolidated, let dry, then flip it over and do the other side. And if you get drips etc around the support area (very common), that's fine, just clean it up with acetone and then brush on a final coat of butvar. That's the appeal of using a reversible consolidant. Most mistakes can be easily corrected.

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I'd try to avoid the support/contact area, and get the top side well consolidated, let dry, then flip it over and do the other side. And if you get drips etc around the support area (very common), that's fine, just clean it up with acetone and then brush on a final coat of butvar. That's the appeal of using a reversible consolidant. Most mistakes can be easily corrected.

Awesome and thanks to everyone. I am cleaning the pieces now.

After reading some posts on "white haze after using Butvar-76" I assume I should "tent" the bones after application to slow down the evaporation process correct?

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I don't know about tenting, but definitely make sure they're dry, and do it on a non-humid day.

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Thought I would update everyone on my progress of my first major bone-prep. work on this baleen jaw piece.

I have cleaned the faces completely, and decided to leave some of the crevices with the original calvert clay material for support. The lovely brown material is starting to show through and there is some wonderful color patterning on the back, as well as some other features which have shown themselves - and which I will display in another set of images.

After cleaning and dehydrating, I butvar-76'ed the piece, impregnated it with plastic, and gently re-brushed the surface gently with a tiny amount of acetone to clean up the faces and make the drying a bit more homogeneous.

I have then repaired the two segments (cf. original images), bonding them back together with cyanoacrylate gel. The fit is tight, but there are some areas that could be filled in.

I still have a bit more to do, but am pleased so far. Once I do a tad bit more touch-up, I am going to make a trip to calvert cliffs, to hunt more fossils, but to also get some more clay matrix, which I will blend into a thick paste with PVA to fill in the cracks on the remainder of this piece. She then will be displayed mightily on our mantle.

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Thanks everyone for their information and comments, it is truly appreciated!

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You have every right to be pleased; you've done a terrific job, and it looks great!

Is this really your first time at this?!

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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