The six commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Elements less commonly recognised as metalloids include carbon, aluminium, selenium, polonium, and astatine. On a standard periodic table all of these elements may be found in a diagonal region of the p-block, extending from boron at one end, to astatine at the other. Some periodic tables include a dividing line between metals and nonmetals and the metalloids may be found close to this line.