Maya blue is an artificial pigment fabricated by the Maya in the early first millennium AD. The pigment was used in Prehispanic times from the southern Maya region to most Mesoamerican cultures. Maya blue is made from indigotin mixed with palygorskite. This light blue pigment is surprisingly resistant to degradation in adverse environmental conditions, as it is unaffected by the attack of acids, alkalis, oxidants, reducing agents and organic solvents. Scientists do not fully agree in the mechanism of this organoclay interaction. The fabrication and distribution of this pigment probably required a sophisticated technical and commercial infrastructure.This chapter reviews the present knowledge on Maya blue. The first part corresponds from its rediscovery in 1931 to the current studies, followed by a review of the properties of Maya blue, including structural and organoclay interaction mechanisms. Archaeological artefacts containing Maya blue helped in understanding the cultural and economic links of the Maya with other Mesoamerican cultures.