Origin of Coal Mineral Matter

Because coal is a sedimentary organic rock, there are in general three types of mineral matter occurring  

1) Biogenic mineral matter assimilated by the former plants represents a very small fraction of the inorganic bulk and is inherentiy chat with the organic matrk. 

3) Epigenetic mineral matter is formed from aqueous solutions that penetrated into cracks of the deposit casting, typically carbonates, quartz, sulfides, or salts washed out from adjacent rocks. Epigenetic mineral matter occurs separated from the organic matrbc. 

From a technological point of view, the epigenetic minerals may be separated by float-sink processes using density separation. They are also easier to identify under the microscope. 

Of course, the transition between the ranks is gradual and the influence of neighboring rock is diverse. But because of the different ages, typical groups of minerals can be expected depending on the rank. 

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