Laterite is a tropical residual soil formed by surficial physiochemical processes. In Goa, deep weathering of Precambrian crystalline basement yields ferruginous laterite which is exploited for production of construction stone. Ashlars are produced from laterite quarries by unique extraction methods using mobile circular saw machines. Laterite ashlaring is utilized in the building of houses and walls and evidence of satisfactory performance and durability is provided by historic buildings such as churches, temples and forts that incorporate laterite ashlars in the construction. The geo-engineering significance of certain laterite ashlars lies in their peculiar self-hardening properties. This natural process of self-bonding takes place rapidly at normal temperatures and pressures and appears to depend only on exposure to air. When the self-hardening properties and behaviour of these materials are properly understood, they may provide potential opportunities for development of new techniques for clay soil stabilization.