Colombo is the leading exporter of tea across the globe, as it exports 90% of its production. Indonesia, Nepal, Sri Lanka, Vietnam, Kenya and India are other major exporters of tea. Africa primarily produces cut-tear-curl (CTC) tea. However, tea is chiefly sold through auctions. The major auction centers in the world are Calcutta, Guwahati, Siliguri, Cochin, Colombo, Mombasa and London. Colombo is the major tea auction centre in the world while Guwahati is the main CTC tea auction centre in the world. The most important broking houses are J. Thomas & Co., Carrit Moran and Contemporary Target. The main tea importers are UK, Pakistan, U.S.A., CIS, Egypt and Iran. The most important markets for superior quality teas are UK and Germany. Generally tea can be classified into two categories; green and black. . Black tea is of two types, Orthodox or Cut, Tear and Curl (CTC) depending on processing of green leaf. China accounts for nearly 70% of the total tea world production.