Australia is the fourth-largest coal producing country in the world.

In 1987 Wyoming became the largest coal producing state.

By 2010 coal produced over a fourth of the world's energy, and by 2050 is expected to produce about one-third.

Spain was ranked as the 30th coal producing country in the world in 2010.

In China, coal also produces sulfur dioxide, the source of acid rain.

Both burn polluting brown coal to produce electricity for this energy-hungry part of the country.

Harrison County was a top coal producing county in Ohio.

Canada was ranked as the 15th coal producing country in the world in 2010, with a total production of 67.9 million tonnes.

Russia was ranked as the 5th coal producing country in the world in 2010, with a total production of 316.9 million tonnes.

The coal produced was of a very poor quality and was of little value to householders.