Guiana Shield Guiana Shield The Guiana Shield is one of the three cratons of the South American Plate. It is a 1.7 billion-year-old Precambrian geological formation in northeast South America that forms a portion of the northern coast. The higher elevations on the shield are called the Guiana Highlands, which is where the table-like mountains called tepuis are found. The Guiana Highlands are also the source of some of the world's most spectacular waterfalls such as Angel Falls, Kaieteur Falls and Kuquenan Falls. The Guiana Shield underlies Guyana (previously British Guiana), Suriname (previously Dutch Guiana) and French Guiana (or Guyane), most of
British Guiana in the Anglo-Dutch Treaty of 1814. The UK continued separate administration of the individual colonies until 1822, when the administration of Essequibo and Demerara was combined. In 1831, the administration Essequibo-Demerara and Berbice was combined, and the united colony became known as British Guiana. The economy of British Guiana was completely based on sugarcane production until the 1880s, when falling cane sugar prices stimulated a shift toward rice farming, mining and forestry. However, sugarcane remained a significant part of the economy (in 1959 sugar still accounted for nearly 50% of exports). Under the Dutch, settlement and economic activity was concentrated