Geodized ?

[Rockwood]

This was found in loose material falling from an exposure of Silurian aged The Forks turbidite. Carbonate nodules full of crinoid fragments are common in it, but what happened to this one ?

I did notice what I assumed was volcanic intrusion nearby. I didn't give it much thought at the time, but it could be worth consideration.

Photographed on snow. (still winter here )

[DPS Ammonite]

It looks like a void in the rock was filled by white quartz on the outside and yellowish calcite in the center.

[Ludwigia]

I agree with the above diagnosis.

[Rockwood]

Is there any indication of the conditions at the time ? Could it be determined if it was cool and colloidal in nature, filled shortly after deposition, or precipitated from hot fluid during a later intrusion ?

[ynot]

To Me it looks like a weathered limestone with calcite on it. Are there any limestone caverns in the area?

Check hardness and do a vinegar test (take small piece from different areas of the stone.).

[JohnBrewer]

11 hours ago, Rockwood said:

This was found in loose material falling from an exposure of Silurian aged The Forks turbidite. Carbonate nodules full of crinoid fragments are common in it, but what happened to this one ?

I did notice what I assumed was volcanic intrusion nearby. I didn't give it much thought at the time, but it could be worth consideration.

Photographed on snow. (still winter here )

I like that, cool find!

[Rockwood]

2 hours ago, ynot said:

Are there any limestone caverns in the area?

No. They are just, on average, turnip sized blobs, thousands of them in a tall ledge that has a railroad cut through it. Many are recognizable as tabulate corals, rugose horns, bryozoans, and the like. Not far to the east there is over one hundred feet of water in Moosehead lake.

[abyssunder]

Geodized (silicified) rugose coral fragment crossed my mind.

 

[Rockwood]

42 minutes ago, abyssunder said:

Geodized (silicified) rugose coral fragment crossed my mind.

There are suggestions of rod like shapes that could correspond to the trace fossils (img.1841) that are common in horn corals in this area. 

[Malone]

In the first two pictures there are a couple obround shapes that look like egg sacks. Just an observation, I am not suggesting they are.

[FossilSniper]

The crystalization in the pictures is definitely a least part calcite. There may be some quartz in there, but I am sure about my calcite assumption, 

as I have found calcite crystals in various fossil orthocones and brachiopods- which are in fact very beautiful, as they are actual fossil geodes. 

Sadly, these wonders aren't on the level of pyritized fossils, but they are sure candidates to take home from a fossil trip!