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Western Maryland Crinoids


smokeriderdon

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Many years ago I was lucky enough to collect a site in Western MD that produces complete crinoids. Considering this is Maryland we are talking about, that's really special! Having finally moved into a house where I could rescue my collection from storage, I figured I would take some pics of these cool fossils. The formation they come from is the Marcellus, a middle Devonian shale formation. The first four specimens are Arthroacantha punctobrachiata...

Crinoid1a.jpg

Crinoid1b.jpg

Crinoid1c.jpg

What I find interesting here is that the stem is not preserved, you only have a cast. It was filled with mud that washed right out. Yet the calyx and arms are preserved.

Same thing here...

Crinoid2a.jpg

Crinoid2b.jpg

Crinoid2c.jpg

The next two, the calyx is there, but the arms have not preserved like the first two, or were washed away...

Crinoid4.jpg

Crinoid5a.jpg

Crinoid5b.jpg

This last one seems to be a different species. The calyx is much smaller in proportion than the others. Two species come from this site, the second being Lasiocrinus scoparius. I am presuming that is what this one is...

Crinoid3a.jpg

Crinoid3c.jpg

Crinoid3b.jpg

And thats them. Hope you liked. :)

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I enjoyed seeing those pieces very much. I am struck by their beauty.

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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Yeah, buddy! Maryland crinoids are pretty special :)

"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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Those are exceptional!

I take it this material is very brittle?

Thanks for posting these.

Regards,

    Tim    -  VETERAN SHALE SPLITTER

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Thanks guys. :)

Yeah, the shale is very fissile and the preservation of the arms is punky. Easily flaked off or washd away. Hence the HEAVY application of PVA giving that shine. But rather the shine than broken fossils.

As is, the crack running through the first one widened in storage. That was a full split that I glued back together almost perfectly. In the time it sat in the box it separated. So much for super glue, eh?

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In case the shale deteriorates over time, would it be feasible to cover the crinoids in plaster, and then remove the shale from the other side. That's the trick we do with fish, etc. from the Cretaceous chalk.

Context is critical.

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Missourian, the shale, while fissile, is holding together nicely (with the exception of that blasted crack). These were collected back in the 90's, so I think they will be OK as far as that goes. But that is something I will have to keep in mind if I ever have an issue like that.

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How wonderful!!! Yet another feast for the eyes and mind!

"The road to success is always under construction." Author Unknown.

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Nice ones, good to see rare stuff like this. There is one on ebay right now from that same place I think.

Too bad you had to slather it so thickly, though, the shine makes it difficult to see detail in photos.. is there a way to lift some of that off with acetone perhaps, without ruining the detail?

As for the crack, did you store them in a cool/damp place? Maybe you had no choice but the key to keeping fossils (esp. glued ones) stable is a stable temp. and humidity.

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Most of the time it was in stable conditions. The entire collection did spend a year in questionably temp controlled storage unit. Also the place where I had a couple riker mounts stolen from the unit when they became over zealous with cutting the lock when I was 3 weeks late with a payment. Anyway, I didn't think humidity would effect super glue as it does Elmers or the like.

Unfortunately, the arm preservation is VERY punky. You could wipe out all surface details with a swipe of a tooth brush. I would be willing to be the third and fourth specimens had layers of arms as well, but being partially exposed they got washed away fairly quickly. Acetone would indeed remove the PVA, but given their original preservation, I really would not feel good about doing that.

I am going to see if I can find that on Ebay, but if you could post a link, that would be marvelous.

OK, so this is the only one from MD I could find... http://www.ebay.com/itm/Devonian-Anthrocantha-crinoids-from-Indian-Springs-Formation-Maryland-/271119935720?pt=LH_DefaultDomain_0&hash=item3f2001e8e8 He lists that being from the Indian Springs formation. I don't know if that is slightly older or younger than the Marcellus formation where mine came from. To the best of my knowledge, only the Marcellus is exposed there, maybe a bit of the Mahantango. I wouldbe interested to find out just where that one comes from. Though mine are a lot nicer. ^_^

Edited by smokeriderdon
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Those are very cool! Glad you were 'reunited' with them to share with us. :)

Edited by Bullsnake

Steve

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I am going to see if I can find that on Ebay, but if you could post a link, that would be marvelous.

OK, so this is the only one from MD I could find... http://www.ebay.com/...m3f2001e8e8 He lists that being from the Indian Springs formation. I don't know if that is slightly older or younger than the Marcellus formation where mine came from. To the best of my knowledge, only the Marcellus is exposed there, maybe a bit of the Mahantango. I wouldbe interested to find out just where that one comes from. Though mine are a lot nicer. ^_^

Sorry I got back too late but yes that was the one I saw.

I wonder if something like PaleoBond would be able to stabilize things like these before extraction without leaving so much of a goopy-looking sheen on it, because it's thinner and designed to readily soak into cracks and pores and set quickly. The only problem I find is the limited shelf-life as I didn't need to use mine often enough (turned gelatinous). Otherwise you might try it next time you have the opportunity.

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  • 3 years later...
  • 2 months later...

There are similar crinoids that I have found in the Devonian mahantango fm of Pennsylvania.the first two I was told are arthroacantha sp. but the third is an oddball....don't know what it is IMG_1171.JPGIMG_1667.JPGIMG_3148.JPG

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