The economy is highly dependent on extraction, but primary materials are abundant. Before the discovery of oil, logging was the pillar of the Gabonese economy. Today, logging and manganese mining are the next-most-important income generators. Recent explorations suggest the presence of the world's largest unexploited iron ore deposit. For many who live in rural areas without access to employment opportunity in extractive industries, remittances from family members in urban areas or subsistence activities provide income.