Thread: Large, Unidentified Rock?

Please see my unidentified, rare & unusual rock photo, here attached. The rock is brick-red in color, is very-very heavy for its size, about 13 inches across & 3 inches thick. Geologists at the University of Idaho could not identify it. It looks much like a large cow-patty.....could it be a corpolite (Dinio Dung)? I bought this at a road-side rock shop in Arkansas about 20 years ago. The owner of the rock shop said he got it mixed in with a trade & had no idea what it was.

Can any one help me to identify it? I had given up identifying the rock, when I recently found a photo of a "Stone Gong Holy Stone" from a holy cave Laos. They looked very similar.

Can anyone identify it for me?

Thanks,
corlar@hotmail.com

Are the convex parts of the facing side concave on the opposite side?

Yes, the oppisite side is more concave (the oppisite of the shown side). However, it is not flat, as I would think a mud concretion would be.

I have received one reply, identifying the rock as a common "mud concreation".

All feedback & input is greatly appreciated.

Thanks,
Lloyd

My first guess was a concretion as well, but the few I've seen have been flat on the resting side.

I agree with flick, a photograph of the opposite side would be very helpful, and my initial reaction is that its a concretion of some type

If I can remember, I will take a photo, or two tonight & send it out tomorrow.

Thanks,
Lloyd

I still don't believe that meteorite came from Mars.

I have finally taken more photos of my mystery rock. I do have my doubts about it being a concretion & lean more toward a corpolite (Dino Dung). See photos, which show that the backside is not flat, etc., here attached.

Lloyd

Ah... good. We don't like a flat backside...

I took better measurements....the rock is approximately 11 to 12 inches across and about 3 inches thick. It weighs an incredible 25 pounds. See attached photos of edge view of the rock.

To me it looks very much like a classic ironstone concretion based on the rounded nature of both sides, and the notably heavy weight. If you are thinking cow patty like look for a herbivorous dinosaur coprolite, the back should be flat and there should be visible plant matter, neither of which are present on the specimen. (Remember coprolite is a term for fossil dung of all ages, not just dinosaurs) With out knowing where it is from or what age it dates too, there is no way to ascribe it to dinosaurs.