21821
Formation of Aragonitic Layered Structures from Kaolinite and Amorphous Calcium Carbonate Precursors .
 Kaolinite, Calcium Carbonate
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Kaolinite, Calcium Carbonate