Complex iron smelting and prehistoric culture in Tanzania.

Western scientists and students of history have long explaind th iron bloomery process by evidence available from European archeology. Ethnographic, technological, and archeological research into the technological life of the Haya of northwestern Tanzania show that these people and their forebears 1500 to 2000 years ago practiced a highly advanced iron smelting technology based on preheating principles and, as a result, produced carbon steel. This sophisticated technology may have evolved as an adaptation to overexploited forest resources. These discoveries are significant for the history of Africa and the history of metallurgy.