Bird egg fossils? I'm a new member.

[mtgoldrush]

Hello,  I found these fossilized 'eggs' taped together at a pawn shop in Kalispell, Montana.  I know nothing about them but they are really cool!  

 

Does anyone know what they are?  The more oval one is about 2" long by 1.5" wide.  The more round one is about 1-9/16" x 1-13/16".  They were sliced in half when I found them.  The one that looks slightly developed ha some missing 'yoke' around the center small circle but is close to fully intact.

 

They are fascinating but I don't know much.  I'm a newbie.

 

Thank you for any help.

[Troodon]

Welcome to the forum.  I believe what you have is a concretion not an egg, sorry.  Eggs typically have eggshell material visible a few millimeters thick.

[-Andy-]

I agree with Troodon. This is not a fossilized egg. It lacks eggshells, and is of the wrong shape. Also, yolk do not get preserved.

[Bobby Rico]

Welcome to TFF two very beautiful concretions .

[Fruitbat]

Welcome to The Fossil Forum!  I'm afraid I'm going to have to agree with the others...not eggs.

 

-Joe

[ynot]

Welcome to TFF!

Yep, not eggs.

They look like unique jasper nodules. It should be possible to determine a location of origin from jasper/agate collectors.

Would look real nice polished.

[mtgoldrush]

Thank you all for your help.  It's easy to see how they can be mistaken for eggs.  I just tried to do a little research on concretions and I guess they form with/from all kinds of minerals.  Very interesting.  I do appreciate all of your input.

I might look into polishing them.  Good idea.  The darker one has almost a dark purple translucence.  

[MarcoSr]

Below is a picture of an Oligocene bird egg from Nebraska.  You can see the thin eggshell on most of the egg.

 

 

Below are pieces of eggshell from the Oligocene of Nebraska:

 

 

 

 

 

Marco Sr.

[Bobby Rico]

3 hours ago, mtgoldrush said:

Thank you all for your help.  It's easy to see how they can be mistaken for eggs.  I just tried to do a little research on concretions and I guess they form with/from all kinds of minerals.  Very interesting.  I do appreciate all of your input.

I might look into polishing them.  Good idea.  The darker one has almost a dark purple translucence.  

You can polish rock with different grades wet and dry paper. 

[Ludwigia]

I agree with ynot. They are Jaspis nodules, which is not quite concretion.