Generally speaking the fine particle size of metakaolin produces a seeding of the cement reaction and therefore accelerates most cements.

The pozzolanic reaction will also form more CSH* bringing an earlier strength development.

This is especially welcome with composite cements.

*CSH - calcium silicate hydrate

more info: Dr. Denis Bezard - are-questions-xya34[at] - phone: +43 (0)2252 45970