Cant find comparable, need help!

[Nkouba]

Hey all this is my first time posting here! I found a fossil (i think) that i need some help identifying. Its unlike most fossils i have seen. I work in landscaping so i see a lot of rocks, this one was different and appeared to have all sorts of shells and mollusks trapped inside. I cracked it open to find it was full of bones, iridescent bones that looked like an oil sheen had dried over them. I have tried to look up opalization but find mostly plants and nothing really comparable. I need help! More pictures available on request. The pictures do no capture the true sheen of the bones and some of the opal looking substance has started to oxidize i think. You can see where it is starting to peel away. Some of the bones that cracked in half revealed more fossils inside the bones including a large grub worm looking thing sticking out of one. I was only able to fit these 2 pictures per the limit, just ask for more. Thanks for any help!

[Darktooth]

The long cylindrical shape objects appear to be cephalopods. The small round objects may be some type of brachiopod. Can you take some more pics and try to focus on the fossils themselves and not the entire rock? Also where was this found?

[Darktooth]

Almost forgot, welcome to the forum from New York! 

[minnbuckeye]

These cephalopods from Graf Iowa are somewhat similar: 

 

But my gut instinct leans away from such an ID.

[Nkouba]

Heya,

I found this in at a Minnesota Gravel Pit. I believe the rock we get comes from Elk River, MN...although i cant be 100% certain. Here is an up close of the largest Cylindrical object that broke when i cracked the rock. It has what appears to be pitting on the side and a grub also inside. Im not really sure how to make my pictures smaller easily so ill just post here for now? Let me know if im breaking rules or if there is maybe a better way! I also noticed some crystalization in the middle of one of the stalks..greenish color

[Nkouba]

These are really the closest my camera can get in focus sadly

[abyssunder]

The specimens in question are Baculites. Don't know which species.

[Nkouba]

Wow. After some research i have to agree, they do appear to be baculites. Thank you much all!

[Yvie]

Welcome,interesting piece.Any chance of a picture of the grub?

[Plax]

not from Minnesota I suspect...

[Dsailor]

those are awesome

[FossilDAWG]

Where did you find this fossil?  As abyssunder says, the cylindrical fossils are Baculites, a straight-shelled ammonite.  The "sheen" is the original nacre of the shell.  The association of Baculites with small clams is typical of some concretions from the Pierre Shale and it's equivalent the Bearpaw Shale, and Fox Hills Formation , all Upper Cretaceous formations exposed in the Dakotas, Montana, Colorado, Wyoming, and in Saskatchewan and Alberta to the north.  These formations are well known for the exceptional quality of their ammonite fossils.  Such concretions are not known to occur in Minnesota, although there is some older Cretaceous exposed in the Iron Ranges area.

 

Don

[Nkouba]

The exact location it was found, was Buffalo, Minnesota in a large pile of rock..However that rock was delivered there by the company "Plaisted". They are a gravel pit operation based out of Elk River MN. I know they produce their own rock from the pit...I cannot with certainty say this rock came from their pit, but i cant imagine they are importing rock given the circumstance. Here is a picture of the "grub" per request. After researching though i think its just a shell..the coloring of white to black made it appear modern grub like =). I think i might try to remove some of the concretion to better expose some of the Baculite....but im apprehensive as i do not want the nacre to degrade. Any ideas?

[Plax]

scaphitid ammonite

[abyssunder]

I agree. Those Baculites are usually associated with Scaphites, so it could be very well one of that.

 

Reading Sloan's document I find this on page 27: " Another Niobrara ammonite, Baculites gracilis, author Shumard, was recovered from a well near the town of Mountain Lake in T. 106 N., R. 35 W. in southeastern Cottonwood County. " - R. E. SLOAN. 1964. THE CRETACEOUS SYSTEM IN MINNESOTA. MINNESOTA GEOLOGICAL SURVEY RI 5

 

Baculites gracilis Shumard = Sciponoceras gracile Shumard

Edited March 15, 2017 by abyssunder
update

[gradykraft]

I would agree, you have baculites and scaphites. Found in central South Dakota in the Fox Hills and Pierre Shale formations, mainly west of the Missouri River. 

[smt126]

I'm quite late to this party, but I stumbled across this page while doing some reading about cephalopods. Those collections look exactly like what I found in Pierre Shale in Montana. Then since it was 5am here and kids are still asleep, decided to read Sloan's paper on Minnesota as well as some other research regarding the geology of Minnesota. I think it's definitely possible that this could be pierre shale that's been buried under glacial deposits in MN. Some of Minnesota was part of the North American Inland Sea during the cretaceous, so it's definitely a possibility. Some of those mining companies do bring in material from other parts of the country though, so there is that possibility as well. I went to their webpage to see if any of their product descriptions matched up with what you would expect pierre shale to look like, but did not find much other than the sale of boulders. I wouldn't be surprised if some of these boulders are actually pierre shale concretions. Unfortunately ordering them will probably yield a lot more plain boulders instead of concretions is my guess. Either way this had to be a fun and exciting discovery. I know I'd be looking through it a lot more.