This is a hatched puffin egg. The beauty of it is mostly in tact. A beautiful speckled puffin egg:

(Photo Source: http://www.flickr.com/photos/28190483@N07/3650595298/)

Both parents take care of the puffin eggs. The male puffins build a nest for the female. Then the female lays generally 1 single egg. Puffin parents are very protective guarding their puffin eggs diligently until they hatch approximately 40-43 days later.