Brown coal (lignite). This form of coal has a high moisture and ash content,and is a more polluting form of coal than the higher (black) grades of coal. It is a sedimentary form of carbon,and the layers of compressed organic matter can be seen in this sample | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wiersma, Dirk |
Bildgröße: | 3780 px × 4792 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |