Round protrusion out of a rock I found in WY

[Mmerc20]

I found this rock on a mountain outside Guernsey WY. The story behind getting it is kinda cool. I had to fly with our battalion commander (I was with the NE National Guard) in an OH-58 and land on a random mountain outside the training base there to assist the CH-47 unit in training to find a "downed" aircraft.

While we sat and waited for our "rescue" I wandered around and saw quite a few of these round protrusions in the rocks up there. This was the only one I could remove as a souvenir. Despite being 8-9 years ago, I never looked in to what it was. I just thought it was cool at the time.

Any ideas?

Mike

[Guest]

Iron concretion form in a matrix of other material--yours is still lodged in the matrix--very cool specimen

[BabaORiley]

Yep, definitely a concretion. If you google image concretions there are some real funky looking ones out there.

[chase]

Nice rock! Hell Gap site is just north of there. I really like the country around there.

[Bone2stone]

David Stone Sweet got it on the nose, when he referred to it as a specimen.

It looks like a fossil wart.

Mmerc20 thank you for your service to our country and your inquisitive nature.

[Mmerc20]

My pleasure bone2stone. I enjoy what I do and have been doing it for 20 years now.

That was probably one of the best flight/trips I've ever made. Had to fly cross-country from eastern NE out to WY. We followed the highway mostly and were able to get an amazing view of chimney rock in the western part of the state. I had some downtime once out there and visited some of the wagon ruts from the Oregon trail. Certainly a beautiful part of the country.