Dinosaur Egg or Concretion?

[AJ Plai]

Hi I have had this supposedly dinosaur egg said to be from the Nanchao Formation in Henan China for quite sometimes and I have never really been sure of it's identity whether if it's just concretion and would like to have some experts and third party opinion on this. Any help IDing this specimen would be appreciated.

 

This is the specimen in question:

 

I have also put the specimen under microscope and tried taking picture of the supposedly shell surface texture but am still not quite sure what to make of it whether if this is a texture of a dinosaur egg specimen?

 

 

I have also taken a picture of the specimen around the edge of what seems to be a shell as well for a closer look in case it helps: 

 

Thanks!!

[Thecosmilia Trichitoma]

It looks like a concretion to me. The "shell" looks too thick, the egg has a weird shape that I haven't ever seen in dinosaur eggs (correct me if I'm wrong with this), and although it has a suggestive texture it is not regular enough nor defined enough to be that of a real egg.

[Fossildude19]

The "shell" looks awfully thick. 

 

I'd have to vote concretion, on this one.    

[Rockwood]

1 hour ago, AJ Plai said:

a closer look

 And it was looking likely to up until then. I'd still like to see what @Troodon says if he's around. The would be shell is thick, but I'm not so sure it's too thick, and the texture is suggestive. 

[Troodon]

Ditto what others have said, the shell looks awfully thick for such a small egg..

[GeschWhat]

Could it be a double egg shell? Maybe that's why it looks thick?

The top part of the shell from the embryonic Oviraptor egg shell in this thread looks pretty thick. 

Obviously not my area of expertise - just thought I would throw it out there. If it were me, I would break off a tiny bit of the shell on the underside and put it in vinegar. I have only worked with bits of raptor and sauropod egg shell, but doing this seemed to reveal a very well defined shell structure.