Although they are the same size, diamond prices can still differ because they also depend on the other three factors in GIA's 4Cs standard: Cut, Color, and Clarity, along with some other factors such as fluorescence and GIA certification,...
A diamond with an excellent cut, whiter color, and fewer inclusions will be rarer, reflect light more brilliantly, and therefore have a higher value even if it is the same size as another stone.
