Santolea was acquired by Minera Sabater to broaden its range of clays. The San Antonio deposit yields clays with different mineral content from those found in the other mines: they have a higher melting content, which improves water absorption.

The deposit lies on the Utrillas facies, dating from the Albian Age. Its sedimentary features have been shaped by the existing paleogeography, and it is included in the so-called Cubeta de Castellote .