Unknowneggs

Unknowneggs are natural blocks, which can be found at the Nesting Grounds.

Nesting Grounds
The area is said to be nesting ground for big dinosaurs.

Triva

 * The game says, that they were eggs from a big dinosaur species, but eggs closely resemble those of xenomorphs (ovomorph), and the cracking noise heard within the cave is the same as that heard in the film Alien (the first appearance of the xenomorph).