The discovery of XRay Difraction by Laue in the 1912 have an important repercusión in Spain. But in the 1924, Martin Cardoso, a Spanish young postgraduate, that work in the MineralogicaI Institute of Leipzig (Germany), determinate the structure of Epsomite. When Martin Cardoso return ed to Spain in the 1929 gone a Course abou t " The application o f XRay Difraction to the Mineralogical Studies Some original works about epitaxic growth of Kyanite (100), over Staurolite (010), the crystal structure of Clauberite,.. are described in this paper