Chemical element native solid elements occur in alloys, such as that of iron and nickel. The history of the discovery and use of the elements began with primitive human societies that found native elements like carbon, sulfur, copper and gold. Later civilizations extracted elemental copper, tin, lead and iron from their ores by smelting, using charcoal. Alchemists and chemists subsequently identified many more; all of the naturally occurring elements were known by 1950. The properties of the chemical elements are summarized in the periodic table, which organizes the elements by increasing atomic number into rows ("periods") in which the columns ("groups") share
Group (periodic table) Group (periodic table) In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table, and the f-block columns (between groups 3 and 4) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e., the same core charge), as most chemical properties are dominated by the orbital location of the outermost electron. There are three systems of group numbering. The modern numbering "group 1" to "group 18" is