Clay

Fine-grained sediments less than 0.0039 mm in size.

 

A group of rock-forming, hydrous aluminium silicate minerals that are platy in structure and can form by the alteration of silicate minerals like feldspar and amphibole. Common examples include chlorite, illite, kaolinite, montmorillonite and smectite.

 

 

For further information: the definition of the 1up info Encyclopedia

 

 

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