The Penedo do Sino (Bell boulder) is a typical granite weathering landform showing a pedestal shape. These landforms can be up to a few meters large, are slightly elevated from the surrounding surface, and show the shape of a mushroom, with a harder and more massive upper section, and a thinner more weathered base. The most likely explanation for the origin of these landforms is that the massive and more resistant upper sector was exposed above the soil surface, whereas the current peduncle formed below the surface, buried in the regolith (from the granite weathering) and subject to moister conditions that accelerated the weathering. The present pedestal shape resulted from the later removal of the regolith by erosive processes.