| Early history | The elements carbon, sulfur, iron, tin, lead, copper, mercury, silver, and gold are known to humans. |
| Pre-a.d. 1600: The elements arsenic, antimony, bismuth, and zinc are known to humans. | |
| 1669 | German physician Hennig Brand discovers phosphorus. |
| 1735 | Swedish chemist Georg Brandt discovers cobalt. |
| c. 1748 | Spanish military Leader Don Antonio de Ulloa discovers platinum. |
| 1751 | Swedish mineralogist Axel Fredrik Cronstedt discovers nickel. |
| 1766 | English chemist and physicist Henry Cavendish discovers hydrogen. |
| 1772 | Scottish physician and chemist Daniel Rutherford discovers nitrogen. |
| 1774 | Swedish chemist Carl Wilhelm Scheele discovers chlorine. |
| 1774 | Swedish mineralogist Johann Gottlieb Gahn discovers manganese. |
| 1774 | English chemist Joseph Priestley and Swedish chemist Carl Wilhelm Scheele discover oxygen. |
| 1781 | Swedish chemist Peter Jacob Hjelm discovers molybdenum. |
| c. 1782 | Austrian mineralogist Baron Franz Joseph Müller von Reichenstein discovers tellurium. |
| 1783 | Spanish scientists Don Fausto D'Elhuyard and Don Juan José D'Elhuyard, and Swedish chemist Carl Wilhelm Scheele discover tungsten. |
| 1789 | German chemist Martin Klaproth discovers uranium. |
| 1789 | German chemist Martin Klaproth discovers zirconium. |
| 1791 | English clergyman William Gregor discovers titanium. |
| 1794 | Finnish chemist Johan Gadolin discovers yttrium. |
| 1797 | French chemist Louis-Nicolas Vauquelin discovers chromium. |
| 1798 | French chemist Louis-Nicolas Vauquelin discovers beryllium. |
| 1801 | English chemist Charles Hatchett discovers niobium. |
| 1801 | Spanish-Mexican metallurgist Andrés Manuel del Río discovers vanadium. |
| 1802 | Swedish chemist and mineralogist Anders Gustaf Ekeberg discovers tantalum. |
| 1803 | English chemist and physicist William Hyde Wollaston discovers palladium. |
| 1803 | Swedish chemists Jöns Jakob Berzelius and Wilhelm Hisinger, and German chemist Martin Klaproth discover black rock of Bastnas, Sweden, which led to the discovery of several elements. |
| 1804 | English chemist and physicist William Hyde Wollaston discovers rhodium. |
| 1804 | English chemist Smithson Tennant discovers osmium. |
| 1804 | English chemist Smithson Tennant discovers iridium. |
| 1807 | English chemist Sir Humphry Davy discovers potassium. |
| 1807 | English chemist Sir Humphry Davy discovers sodium. |
| 1808 | English chemist Sir Humphry Davy discovers barium. |
| 1808 | English chemist Sir Humphry Davy discovers strontium. |
| 1808 | English chemist Sir Humphry Davy discovers calcium. |
| 1808 | English chemist Sir Humphry Davy discovers magnesium. |
| 1808 | French chemists Louis Jacques Thênard and Joseph Louis Gay-Lussac discover boron. |
| 1811 | French chemist Bernard Courtois discovers iodine. |
| 1817 | Swedish chemist Johan August Arfwedson discovers lithium. |
| 1817 | German chemist Friedrich Stromeyer discovers cadmium. |
| 1818 | Swedish chemists Jöns Jakob Berzelius and J. G. Gahn discover selenium. |
| 1823 | Swedish chemist Jöns Jakob Berzelius discovers silicon. |
| 1825 | Danish chemist and physicist Hans Christian Oersted discovers aluminum. |
| 1826 | French chemist Antoine-Jérôme Balard discovers bromine. |
| 1828 | Swedish chemist Jöns Jakob Berzelius discovers thorium. |
| 1830 | Swedish chemist Nils Gabriel Sefström rediscovers vanadium. |
| 1839 | Swedish chemist Carl Gustav Mosander discovers cerium. |
| 1839 | Swedish chemist Carl Gustav Mosander discovers lanthanum. |
| 1843 | Swedish chemist Carl Gustav Mosander discovers terbium. |
| 1843 | Swedish chemist Carl Gustav Mosander discovers erbium. |
| 1844 | Russian chemist Carl Ernst Claus discovers ruthenium. |
| c. 1861 | German chemists Robert Bunsen and Gustav Kirchhoff discovers cesium. |
| c. 1861 | German chemists Robert Bunsen and Gustav Kirchhoff discovers rubidium. |
| 1861 | British physicist Sir William Crookes discovers thallium. |
| 1863 | German chemists Ferdinand Reich and Hieronymus Theodor Richter discovers indium. |
| 1875 | Paul-émile Lecoq de Boisbaudran discovers gallium. |
| 1878 | Jean-Charles-Galissard de Marignac receives partial credit for the discovery of ytterbium. |
| 1879 | Swedish chemist Per Teodor Cleve discovers holmium. |
| 1879 | Swedish chemist Per Teodor Cleve discovers thulium. |
| 1879 | Swedish chemist Lars Nilson discovers scandium. |
| 1879 | Swedish chemist Lars Nilson receives partial credit for the discovery of ytterbium. |
| 1880 | French chemist Paul-Émile Lecoq de Boisbaudran discovers samarium. |
| 1880 | French chemist Jean-Charles-Galissard de Marignac discovers gadolinium. |
| 1885 | Austrian chemist Carl Auer (Baron von Welsbach) discovers praseodymium. |
| 1885 | Austrian chemist Carl Auer (Baron von Welsbach) discovers neodymium. |
| 1885 | German chemist Clemens Alexander Winkler discovers germanium. |
| 1886 | French chemist Henri Moissan discovers fluorine. |
| 1886 | French chemist Paul-Émile Lecoq de Boisbaudran discovers dysprosium. |
| 1894 | English chemists Lord Rayleigh and William Ramsav discover argon. |
| 1895 | English chemist Sir William Ramsay and Swedish chemists Per Teodor Cleve and Nils Abraham Langlet discover helium. |
| 1898 | English chemists William Ramsay and Morris Travers discover krypton. |
| 1898 | English chemists William Ramsay and Morris Travers discover neon. |
| 1898 | English chemists William Ramsay and Morris Travers discover xenon. |
| 1898 | French physicists Marie and Pierre Curie discover polonium. |
| 1898 | French physicists Marie and Pierre Curie discover radium. |
| 1899 | French chemist André Debierne discovers actinium. |
| 1900 | German physicist Friedrich Ernst Dorn discovers radon. |
| 1901 | French chemist Eugène-Anatole Demarçay discovers europium. |
| 1907 | French chemist Georges Urbain discovers lutetium. |
| 1907 | French chemist Georges Urbain receives partial credit for the discovery of ytterbium. |
| 1917 | German physicists Use Meitner and Otto Hahn discover protactinium. |
| 1923 | Dutch physicist Dirk Coster and Hungarian chemist George Charles de Hevesy discover hafnium. |
| 1925 | German chemists Walter Noddack, Ida Tacke, and Otto Berg discover rhenium. |
| 1933 | French chemist Marguerite Perey discovers francium. |
| 1939 | Italian physicist Emilio Segré and his colleague Carlo Perrier discover technetium. |
| 1940 | Edwin M. McMillan (1907-91) and Philip H. Abelson prepare neptunium. |
| 1940 | Dale R. Corson, Kenneth R. Mackenzie, and Emilio Segré discover astatine. |
| 1940 | University of California at Berkeley researcher Glenn Seaborg and others prepare plutonium. |
| 1944 | University of California at Berkeley researchers Glenn Seaborg, Albert Ghiorso, Ralph A. James, and Leon O. Morgan prepare americium. |
| 1944 | University of California at Berkeley researchers Glenn Seaborg, Albert Ghiorso, and Ralph A. James prepare curium. |
| 1945 | Scientists at the Oak Ridge Laboratory in Oak Ridge, Tennessee, discover promethium. |
| 1949 | University of California at Berkeley researchers prepare berkelium. |
| 1950 | University of California at Berkeley researchers Glenn Seaborg, Albert Ghiorso, Kenneth Street, Jr., and Stanley G. Thompson prepare californium. |
| 1954 | University of California at Berkeley researchers prepare einsteinium. |
| 1954 | University of California at Berkeley researcher Albert Ghiorso and others prepare fermium. |
| 1960s & 1970s | Researchers at the Joint Institute of Nuclear Research, in Dubna, Russia; the Lawrence Berkeley Laboratory at the University of California at Berkeley; and the Institute for Heavy Ion Research in Darmstadt, Germany, continue to prepare new transfermium elements. |
