Can anyone tell me why it looks like stones in my Eggs?

[Breesanchez94]

There’s about 3 small hard rock-like substances in my eggs. The rooster is separated from my hens and I know they aren’t fertile so I’m not sure what this is. Any suggestions? And are they edible?

 

[AlleysChicks]

Meat spot. They are edible, I pick them out though if I find them.