Metakaolin is not a byproduct. It is obtained by the calcinations
of pure or refined Kaolinitic clay at a temperature between 650
0
C and 850 0
C, followed by grinding to achieve a fineness of
700-900 m2
per kg. The resulting material has high pozzolanicity.
Metakaolin is manufactured from pure raw material to strict
quality standards. It differs from other admixtures without
chemical composition. They may also contain active
components (such as sulphur compounds, alkalies, carbon,
reactive silica) which can undergo delayed reactions within