 Extensive underground mining took place in the area and this continued until 1985 during which time the mine at Raub produced nearly 1 million ounces, 85% of the production of Peninsular Malaysia.Another important article of export was tin, which was also mined in a large scale.The tin ore production was primarily concentrated at Sungai Lembing, where during its heyday, the operations saw the excavation of deep shaft mines that were among the largest, longest and deepest in the world.