Earl Grey Tea and Doppio are produced all around the globe. And they change according to region in where they are cultivated. So, the question arises what is Earl Grey Tea and Doppio's differentiating factor?In following section we will take a close look at what is Earl Grey Tea and Doppio color, serving style, types and much more. First thing to know is what are the different types of Earl Grey Tea and Doppio. Well, Earl Grey Tea types include Herbal while types of Doppio are Espresso.