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Gen. et sp. indet.

Bivalvia or pygidium

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Gen. et sp. indet.

Ordovician or Silurian erratic boulder from Poland.

It's not the first time I come across this type of fossil.

Would you say these are bivalves or some big trilobites' pygidia?

IMAG8569.thumb.jpg.61ce9cbddfeb3bfd97d976a73d3ba7a7.jpg

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DevonianDigger

All I see is geology here I'm afraid. Is there a specific spot you're referring to that maybe I am just not seeing?

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Gen. et sp. indet.

Oh, come on. It is a finely laminated (visible on the side of the specimen, not on the photographed surface) rock, and the fragment with growth lines is parallel to the laminae and embeded in one of them, and has some thickness.

IMAG8559.thumb.jpg.be1628be5a67e1d04d064a69c3ab1928.jpg

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Kane

I think I would rule out trilobite pygidium for this one as I'm not aware of any trilobite morphology that would have these striations in the sequence as presented. 

 

I am seeing distinct termination boundaries in your new image that seem to more suggest a fossil, possibly brachiopod or bivalve. Is there more to reveal under prep?

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ynot

Sorry, but I do not see a fossil here.

I am seeing a tumbled rock with a thin mineralized vein, exposed on one side,  that shows some slickensides structures.

There also appears to be discreet iron banding that has oxidized.

The rock is not chert, way to granular for that. The vein looks like a quartz mineral.

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Innocentx

I'm thinking bivalve for the fragment. Is it concave?

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ynot
1 hour ago, Gen. et sp. indet. said:

visible on the side of the specimen, not on the photographed surface

 

Please post pictures that show the other sides of the rock.

Thank You.

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Gen. et sp. indet.
4 hours ago, ynot said:

Please post pictures that show the other sides of the rock.

Thank You.

Underside (dentrites).

IMAG8602.thumb.jpg.5da4e19d794f7c19db4f688ef17ea1c0.jpg

Side (laminae).

IMAG8603.thumb.jpg.eccdbb2c8f1b32a26cfe6adf95890da6.jpg

Brachiopod.

IMAG8607.jpg.90d309d850e9d71f397deac600559fd2.jpg

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ynot

Thanks for the additional pictures.

I agree with the dendrite and brachiopod (or clam) in these pictures.

I would like to see a side view of the part that was originally shown.

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Gen. et sp. indet.

The surface is kinda twisted...

IMAG8612.thumb.jpg.cd7a9de04e3292a64677b07e1ceeb467.jpg

The shell is thin, although distinct when studied in person...

IMAG8627.thumb.jpg.573e3aaee6363f5407b0936130bfd42c.jpg

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westcoast

Is it possible that the curved laminations are a fractured surface revealing the internal sedimentary laminations which are clearly visible on the side?

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ynot

I stick with My original statement, a mineralized vien.

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Innocentx

I think it's preserved periostracum similar to this. When I find myalina bivales, many times it's the periostracum that's preserved.

IMG_4316.JPG

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