Hi Giga, there are 2 ways to use metakaolin to reduce the carbon...

Hi Giga, there are 2 ways to use metakaolin to reduce the carbon foot print of cement &/or concrete.

The first is to create a new cement blend = LC3


The other is to more simply, change the binder ratio that goes into making concrete ie less cement (clinker) and more SCM (metakaolin), the key is to not impact the structural integrity of the concrete & it has been widely proven that the addition of metakaolin actually improves concrete strength are other key characteristics. You mention flyash & slag, hence me snipping the table below which confirms that metakaolin clearly beats both flyash & slag from a pozzolanic reactivity perspective - which is what you need from a SCM.