a) Cleft covers: natural, non-worked slabs, with cleft or chisel-worked visible sides; with a thickness of 3-4-5 cm or more on request. The length can be fixed or varying, the width on request. Cleft headings.

 b) Milled covers: natural, non-worked slabs, with milled visible sides; with a thickness of 3-4-5 cm or more on request. The length can be fixed or varying, the width on request. Milled headings. Moreover, the thickness of the visible sides can be machine-made and chiseled or blazed.