L1 /
17
CH3041
CIA
• Feldspar 1o orthoclase KAlSi3O8
• Clays 2o smectite (montmorillonite)
K+0.5(Al1.75Mg0.25)(Al0.25Si3.75)O10(OH)2
2o kaolinite Al4Si4O10(OH)8
K+0.5(Al1.75Mg0.25)(Al0.25Si3.75)O10(OH)2
2o kaolinite Al4Si4O10(OH)8
• Leaching removes soluble Si(OH)4 and cations and leaves behind the
insoluble Al (under most pH conditions).
Feldspar (1:3: 8) ® smectite
(1:1.9: 6) ®
kaolinite (1:1: 4.5) ® gibbsite Al(OH)3 (1:0:3)
kaolinite (1:1: 4.5) ® gibbsite Al(OH)3 (1:0:3)
