Due to the volcanic nature of the islands, mineral deposits are abundant. The country is estimated to have the second-largest gold deposits after South Africa and one of the largest copper deposits in the world. It is also rich in nickel, chromite, and zinc. Despite this, poor management, high population density, and environmental consciousness have resulted in these mineral resources remaining largely untapped. Geothermal energy, however, is another product of volcanic activity that the country has harnessed more successfully. The Philippines is the world's second-biggest geothermal producer behind the United States, with 18% of the country's electricity needs being met by geothermal power.