Ida-Viru County (Estonian: Ida-Viru maakond), or Ida-Virumaa, is one of 15 counties of Estonia. It is the most north-eastern part of the country. The county contains large deposits of oil shale - the main mineral mined in Estonia. As oil shale is used in thermal power plants, the earth in Ida-Viru contains most of Estonia's energy resources. The capital of the county is the town of Jõhvi which is administratively united with the Jõhvi Parish.