Here is an interesting comparison of eggs. The largest are from Cornish Cross that randomly managed to evade the slaughterhouse. The middle are year old ISA Browns. The smallest are Silver Gray Dorking eggs. They average about >82 grams and are mostly double yolks, 65-70 grams and 49 grams respectively.
The other photo is just a beer
The Silver Grey Dorking's haven't been laying egg's for long, so they should get bigger later.