Sample of coal. Coal is a carbon-based fossil fuel formed mainly from plant remains that have been compacted and hardened. Most coal was formed in the carboniferous era (280 to 345 million years ago) | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library |
Bildgröße: | 4200 px × 4200 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |