Pretty shells

[Jackson g]

21 hours ago, connorp said:

That's a pretty nice and big tooth plate. I might be more inclined to call this Psephodus. It's similar to 58.C below (from the Handbook of Paleoichthyology Vol. 4). Hard to tell without the specimen in hand.

That said, I would try not to get super caught up on trying to identify these crusher tooth plates. There are many undescribed "species" plus morphological variations within "species". I say "species" because many of them are based on only isolated tooth plates, which in some cases likely came from completely different animals. Really a whole messy business.

I do see the resemblance between the two. C is very close in appearance. I really wasn't expecting a perfect match, just a general species or genus to assign to the tooth plate. The thesis I've been reading says pretty much what you're saying, it's a confusing mess, and that no in depth studies of their remains or the Burlington-Keokuk fish bed has been done since the 1905s. A lot of the teeth found they can't ID due to poor preservation too it seems. That's why I posted them here. I'm just happy to find one.

[Jackson g]

Went on an evening hunt for about a hour to split some chert. Sometimes its easier to wack the rock, and repair whatever afterwords. Chert isn't always fun material to work. Heres a few cool blastoids, and a sweet brach I found and fixed.

[Misha]

1 minute ago, Jackson g said:

Went on an evening hunt for about a hour to split some chert. Sometimes its easier to wack the rock, and repair whatever afterwords. Chert isn't always fun material to work. Heres a few cool blastoids, and a sweet brach I found and fixed.

Very cool! 

They look quite thin, are they as fragile as they would seem?

[Jackson g]

[Jackson g]

Note the brachiopod's innards are preserved in this cherty example. I tried to do my best outlining where they are in this split photo, for those who have a hard time seeing it.

[Jackson g]

3 minutes ago, Misha said:

Very cool! 

They look quite thin, are they as fragile as they would seem?

They are extremely fragile and thin! After a year and a half of working this material, I've learned a trick or two I like to think on extracting these delicate steinkerns from cherty limestones. Though sometime it doesn't matter how careful your are, they just crush into nothing. I usually tend to keep a water bottle on me just for transporting these, so I don't ever break them out in the field.

[Jackson g]

Not a fossil, but still pretty cute was this deer fawn I snapped a shot of that was just above one exposure not covered in grass and weeds. Not sure where it's mama was, but it was a pretty bold young buck and tried to approach me. Knowing it's mom wouldn't appreciate my scent, I loudly walked the other way.

[Jackson g]

One last fossil hunt for the week turned up a couple cool results today. 

 

 

First is a little druzy replaced internal small loop of a terebratulid brachiopod I popped out from this piece of chert. These loops supported the lophophore. 

[Jackson g]

Another fine partial Deltodus sp. tooth plate was found weathered free from the limestone.

[Jackson g]

To finish, some scenery. I often like to come to this spot after a good hunt and enjoy myself. There are fossils here too, but its rather unsafe to try and collect here.

[Misha]

3 hours ago, Jackson g said:

Another fine partial Deltodus sp. tooth plate was found weathered free from the limestone.

Lovely tooth!

 

[Tidgy's Dad]

Some great finds, as usual, Jackson. 

[Jackson g]

Got a couple more cool brachiopods from today's lurkings. 

[Jackson g]

[Jackson g]

Find of the day is forsure this terebratulid sp. brach with the small loop support preserved and intact. It's harder to get these ones out from the chert more than anything because the loop is just so small and fragile. Chipped off a little more shell than I wanted to (don't use a pocket knife while out looking still to disect brachs!). It took many a try to get a good photo because the white color kept blending together.

[Wrangellian]

Nice finds, as always, since I last commented. It's nice when you can get something out complete that is normally fragmentary or falls apart, as I know all to well with my local stuff.

Do any of these retain their shell (or replacement), or all steinkerns... for instance, the Platyceras has the appearance of having a positive shell, or is that just an illusion?

I'd still like to get one of those non-Pentremites blastoids from you if you have any to spare (I'll cover costs).

[Jackson g]

On 8/22/2020 at 10:53 PM, Wrangellian said:

Nice finds, as always, since I last commented. It's nice when you can get something out complete that is normally fragmentary or falls apart, as I know all to well with my local stuff.

Do any of these retain their shell (or replacement), or all steinkerns... for instance, the Platyceras has the appearance of having a positive shell, or is that just an illusion?

I'd still like to get one of those non-Pentremites blastoids from you if you have any to spare (I'll cover costs).

Thanks Eric. It's been a great year for fossiling! That platyceras does have a positive shell there, though not the original shell the organism was deceased with. If you look hard you can see in the top right of the photo where some shell is missing, but still preserved the interior. 

 

Shoot me a pm on here and we can arrange something here soon and get you a nice blastoid. I have a good example that I should be able to prep soon, or I have a great steinkern chert example I think you'd really like if you can be pateint enough for it to arrive back in the mail. Unfortunately a trade I did a while back with another member didn't work out well because their post wanted to charge them taxes on my trade, and they considered it merchandise somehow even when marked as a geologic specimen under 50$ (gift). Lesson learned, don't throw out any document from the USPS until both parties receive parcels.

[Wrangellian]

Ah, nice example, even with the missing bit of shell.

I sense that the rules that get enforced are largely up to the whim of the post office worker you get at the time - or the customs agents, whichever. Otherwise I don't understand why something that you've shipped umpteen times before without any issue will suddenly be an issue. Oh well. How much tax would there be on <$50?

Also the recommendations you get vary depending on the clerk too: I've had them tell me that if you mark it as a gift, the customs agents will be suspicious and are just as likely, if not more so, to slap a duty on it, knowing that many people will ship an item of merchandise and mark it as a gift in hopes of avoiding those duties. But others say the opposite - if it's a gift, it's a gift, and not supposed to have any duties. I dunno.

[Jackson g]

The first slab I pulled out today at a new location. Needless to say I was pretty happy, though the rain ended my trip early!

 

In sunlight, magnified 

 

In LED light after some scraping with my pocket knife while out still, couldn't help myself. I'll clean it up further someday when I have more time. I think this one would be better off leaving on the matrix, and scribing around it with some matrix intact, for display purposes. Can't complain when the first fossil of the day is a rare one, especially a Mississippian aged tooth plate.

[Jackson g]

Sara and I went out fossil hunting today. It was our last day, and she must have been my good luck charm!!!

Start:

 

Finish:

 

Composita sp. Brachiopod, Burlington Formation - Henry County, Missouri

[Jackson g]

I've got a couple more of my pretties to share again today! First is this sparkly terebratulid brachiopod with it's small loop preserved. Hard to see it though with all those crystals! An added bonus are those black specks. What I originally thought was dirt is not, they are crystal also! I'm too lazy to check my mineral guide currently, it's been a long day here. Pretty interesting regardless! Names/ID can always be found and labeled later, but the black mineral is exciting to see.

[Jackson g]

That's not the only pretty to flash! Unfortunately, just a flash too of this one. I had set this down because they are so fragile, but couldn't relocate it while I was out collecting. I planned on prepping this tonight along with some others on the list. Not pleased with myself here.  The white loop really popped on the red matrix/ shell. I never find them in the easier to work cherty matrix like this.

[Jackson g]

Well, at least here's one successful prep of today. I try not to choke you all with too many crinoids on this thread, but these are nice. This is one of those nice, fragile steinkerns that are 3-D and removable from its rock 

 

Hard to see in the first photo, but the small geodized brach on the right next to the calyx has the same small black crystals laying inside on the druzy quartz.

[Jackson g]

Last off is a real eye catcher. What's better than a solid, crystalized calyx (I think an Actinocrinitidae crinoid) like this? Its huge, and oh so sparkly. Luckily, I got this out whole from the hard, sticky chert 

[Jackson g]

Well I lied again, I've got another crinoid to share for now. I started working on this last night, but I didn't have time to finish it until today. This big daddy has got to be the biggest crinoid steinkern to date I've cleaned up. Just imagine, this is just the chert replaced mold. The crinoid would have been even bigger in life!

 

The top where the feeding arms would be.

 

Bottom of the calyx.