Ugh, what is this stuff!?

[Empera]

Okay, so for the past month, my Australorp Penelope has been laying eggs with it sees like calcium deposits on the top and sometimes other parts of the egg. It's just on the shell though.

Here's some horrible not close up pictures, my camera doesn't like to zoom.

Can you see the odd shape of the egg? And the clusters of stuff?

Anyways, she eats the same as others. I don't supplement with oyster shells or anything else. Just normal layer feed.

Any suggestions on what it might be and what's causing it?

 

[ScoobyRoo]

My EE's green egg was similar. Just not as much deposits on her egg. She was the only one out of 20 hens that had that. They do get oyster shells though along with free ranging and layer feed. Not sure what it was. I hope someone will know.