Located in the center of a small rocky outcrop formed by two large rocks surrounded by smaller stones. It is a spheroidal granite ball, measuring 1.30 meters high, 2 meters long and 1.50 meters wide, with two incised engravings. The first engraving is located on the northwest side of the rock (facing Arenys de Munt), measures 0.34 meters by 0.21 meters and forms an oval figure with a flat base. At the upper end, a small rectilinear stroke enters the inside of the oval, while at the base there are two more strokes at the ends towards the outside. The second engraving (facing Dosrius) is at the west end, measures 0.34 meters by 0.13 meters and has a ramiform (branch-like) shape.
The element is included within the limits of Parc del Montnegre and the Corridor.
Since the end of the 19th century, this stone has been identified as a dividing landmark between the municipal terms of Dosrius, Arenys de Munt and Sant Vicenç de Montalt. The first deed of settlement in which it appears is from the year 1889 (identified as the seventh mollón between Dosrius and Arenys de Munt and the first between Dosrius and Sant Vicenç de Montalt) and, subsequently, it appears again in 1918 in a new recognition of limits. In both acts, the owner of the area is the Marquis of Aigüesvives and reference is made to the engravings. Several authors attribute a Neolithic chronology to the rock, reused as a landmark for a castle in the Middle Ages. Traditionally, the engraving facing Arenys de Munt has been identified with a horseshoe, although also a boar's hoof and a bell. In 1918, the second engraving was identified as a palm. In reality, the two engravings are term marks, the one on the horseshoe identified with Sant Martí as patron saint of Arenys de Munt (the horseshoe is one of its symbols) and the one on the branch in reference to Dosrius (the palms correspond to the two patrons Saint Iscle and Saint Victoria and have been present in the municipal coats of arms since the 19th century). This last engraving cannot be ruled out as symbolizing the confluence of two streams (Canyamars and Rials streams forming the Dosrius stream). The proposed chronology is related to the heyday of this type of engraving.