Cation exchange capacity (CEC) of mica is

CEC (cation exchange capability), is a measure of negatively charged sites on the surface, which help in holding positively charged ions and nutrients.
It is a calculated value that is an estimate of the soil's ability to attract, retain and exchange cation elements. It is reported in milliequivalents per 100 grams of soil (meq/100 g).
CEC of mica is 0 as the surface charge of clays varies from 0.11 to 0.20.