Basic objective of this lecture is to present Boron Family. The elements in Group 13 are all metals except boron, which is a brittle, black metalloid. This group includes the elements boron, aluminum, gallium, indium, and thallium. All five have three electrons in their outer energy level. Only one member of this family is a metalloid — boron. The elements in Groups 13-18 are not all solid metals like the elements of Groups 1 and 2.