Dear Xinxing,

You can analyze using XRD and XRF methods. The first method presets mineral content and the second one percent of composing oxides.

Best wishes

To dear Jorge Costa-de-Moura

Thank you for your reply. Yes, do you think the existence of micas is one reason for soil exert acid buffer capacity and negative charge. In my work, i want to know the major component of Aluminosilicate in farmland soil. Because the cation exchange capacity was attributed to the negative charge of soil colloid and the reason is isomorphic substitution caused by （Al or Mg）. So your answer is quite useful for me. Can you suggest me a standard chemical which could represent the clay component? Clay is mainly composed of Aluminosilicate (micas, kaolin, Montmorillonite and so on）

To Kenneth M Towe

Got it. Thank you so much.

use XRD and XRF methods

I recommend Hussien's answer

Best Regards

You could try thermal analysis of clay. Kit is simple.