Coal
How did coal form?
Coal is the transformed remains of plants buried in swamp forests hundreds of millions of years ago; its carbon was born in stars and its energy came from the Sun.
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In three stops
Where were its atoms born?
Carbon, coal's main atom, was made inside stars and entered plants through carbon dioxide in the air.
How did it form on Earth?
About 360–300 million years ago (the Carboniferous period) there were vast swamp forests. Dead plants were buried underwater before they could fully rot, turning first into peat and then, over millions of years of heat and pressure, into lignite and hard coal. Most of Türkiye's lignite is much younger.
What did humans make of it?
Coal powered the steam engines of the Industrial Revolution and is still used to make steel. Burning it returns carbon that plants took from the air hundreds of millions of years ago to the atmosphere as carbon dioxide, one of the main causes of climate change.
Did you know?
A lump of coal is really stored sunlight: those trees captured the Sun's energy in chemical bonds through photosynthesis.
See it in the journey: The coal forests (360–300 million years ago) →