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This enabled his assistant Carl-Gustav Mosander to receive early credit for work that Mosander chose not to formally publish until many years later after he had worked out all of the details. Berzelius usually cited articles published in other journals, but he also reported on the work in his laboratory which had not yet been published. This leads to the question of who should be considered the ultimate discoverer of a chemical element? Should it be the first person to describe the initial properties, the one who found the oxide or the metal, the one who separated the element or the first one to publish their results? On the matter of publication, the Swedish chemist Jons Jacob Berzelius published an annual review (equivalent to our present abstract service) during the early nineteenth century.

If a publication was delayed, the discoverer has often historically been "scooped" by another scientist. There are also cases where the honor of discovery is not given to the first person who actually discovered the element but to the first person to claim the discovery in print. In general, the requirements for discovery claims have tightened through the years and claims that were previously accepted would no longer meet the minimum constraints now imposed. This fact was not realized at the time of their discovery, until the English chemist Humphry Davy showed that earths were compounds of oxygen and metals in 1808.Īlthough the atomic weight of an element and spectral analysis of that element were not available in the early days, both of these elemental properties would be required before discovery of the element would be accepted by the latter part of the nineteenth century. The reason for this is that in the case of these rare earth elements, the "earth" now refers to oxides of a metal not to the metal itself. The honor of discovery has often been accorded not to the person who first isolated the element but to the person who discovered the original mineral itself, even when the ore was impure and that ore actually contained many elements. Also in those days, there were many claims, e.g., the discovery of certain rare earth elements of the lanthanide series, which involved the discovery of a mineral ore, from which an element was later extracted. In those early days, atomic weight values were not available, and there was no spectral analysis that would later be supplied by arc, spark, absorption, phosphorescent or x-ray spectra. The method of discovery of the chemical elements in the late eighteenth and the early nineteenth centuries used the properties of the new substances, their separability, the colors of their compounds, the shapes of their crystals and their reactivity to determine the existence of new elements. The basis for the claim of discovery of an element has varied over the centuries. There are also some miscellaneous names as well as some obscure names for particular elements. The names of the various chemical elements come from many sources including mythological concepts or characters places, areas or countries properties of the element or its compounds, such as color, smell or its inability to combine and the names of scientists. As we shall see in the following elemental review, the origin of the chemical elements show a wide diversity with some of these elements having an origin in antiquity, other elements having been discovered within the past few hundred years and still others have been synthesized within the past fifty years via nuclear reactions on heavy elements since these other elements are unstable and radioactive and do not exist in nature. What do we mean by a chemical element? A chemical element is matter, all of whose atoms are alike in having the same positive charge on the nucleus and the same number of extra-nuclear electrons. Holden* National Nuclear Data Center Brookhaven National Laboratory Upton, New York 11973-5000 USA Prepared for the 41st IUPAC General assembly in Brisbane, Australia June 29th - July 8th, 2001 History of the Origin of the Chemical Elements and Their Discoverers