In the work at hand, physical-mechanical property results are given, such as those of resistance to compression, capillary and total water absorption, pore size and distribution, chloride penetration resistance and behaviour in the presence of sulphates, mortars and concretes with metakaolin added (MK). This is produced in Colombia via thermal treatment of highly pure kaolin, whose pozzolanic character was tested by way of chemical techniques (Frattini Test, NTC1512), mechanical trials (ASTM C311) and differential thermogravimetric analysis (DTG).