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native element
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structures of some native elements
structures of some native elementsStructures of some native elements. (A) Close-packed model of simple cubic packing of equal spheres, as shown by iron. Each sphere is surrounded by eight closest neighbours. (B) Close-packed model of the structure of arsenic and antimony. Flat areas represent overlap between adjoining atoms. (C) Partial representation of the structure of diamond. (D) The structure of graphite with sheets perpendicular to thec axis.

native element

chemical element group
Also known as:pure element

native element, any of a number of chemical elements that may occur in nature uncombined with other elements. The elements that occur as atmospheric gases areexcluded.

A brief treatment of native elements follows. For full treatment,seemineral: Native elements.

Of the 90 chemical elements found in nature only 19 are known to occur as minerals. These native elements are commonly divided into three groups—namely,metals (platinum,iridium,osmium,iron,zinc,tin,gold,silver,copper,mercury, lead, chromium);semimetals (bismuth,antimony,arsenic,tellurium,selenium); andnonmetals (sulfur, carbon). In metals themineral structure is usually either cubic close-packed or hexagonal close-packed. The semimetals and nonmetals have more complex structures. Several native elements (e.g., carbon) have one or more polymorphic forms whose occurrence depends on the conditions of formation.

Periodic Table of the elements concept image (chemistry)
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It is virtually impossible to make generalizations as to the occurrence of the native elements. They form under greatly contrasting physicochemical conditions and in all types of rocks. Even a single native element can occur in widelydiverseenvironments. Native iron (kamacite), for example, is found primarily in meteorites. The iron meteorites called hexahedrites are almost completely composed of kamacite, and in those called octahedrites it is the principalconstituent. Although terrestrial native iron is a great rarity, it has been found in igneous rocks (basalts), in carbonaceous sedimentary rocks, and inpetrified wood.

Many of the other metals and certain non-metals are sufficiently abundant to form deposits of commercial importance. Native gold and silver, for example, are the principal ores of these metals.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated byErik Gregersen.

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