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