This is an original Raptor egg from the third Jurassic Park movie. These were produced to fill the Velociraptor nests seen near the beginning of the movie where Alan Grant and others encounter a colony of velociraptor nests.
These screen used eggs are made of solid resin and can be seen in the raptors nests when Billy (Alessandro Nivola) steals two of them. When haunted by raptors throughout the movie who can smell the eggs in Billy’s bag, they eventually realize they must give them back to the raptors if they want to stay alive.