Abstract
Gypsum, relegated in contemporaneous architecture to a secondary auxiliary or decorative role, has been traditionally employed in some parts of Spain for building structural pillars, floors, massive walls, mortars, etc. The authors have studied this gypsum in its several local forms, from its firing in the kiln to the building process in order to unveil the reasons for its excellent structural behaviour. With the first hypothesis, several strength tests with present commercial gypsum have been made at the laboratory. They confirm the extraordinary structural performance of the material, if only some conditions are respected during the building process.
