At breakfast one day, my 4-year-old son was peeling his boiled egg when he noticed something unusual. On the side of the egg was an almost perfect white square with sides about 1 centimetre long. This was enclosed in an oval patch of yellow matter (see photo, left).
Although the yellow patch looked like egg yolk, the egg appeared normal when I cut it in half, and I could not see any connection between the egg yolk in the centre and the yellow patch on the outside.
Does anyone know how this formation was created?
Johan Forsberg, Linköping, Sweden