The periodic table lists 118 known elements. Although all 118 elements, and possibly more, can be produced by natural processes, not all of them are commonly found in natural settings. Each of these elements has a unique... More »

The five most abundant elements in the Earth's crust are oxygen, silicon, aluminum, iron and calcium, in that order. Sodium, potassium and magnesium are also prevalent in the Earth's crust. Carbon, hydrogen, nitrogen, ox... More »

Lithium is never found in its pure form in nature, according to the UC Davis ChemWiki. It is found in igneous rocks combined with other elements, such as aluminum, silicon and oxygen, and in salt water as lithium chlorid... More »

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Hydrogen and ununoctium are two examples of the more than 100 elements that have either been discovered in nature or synthesized by scientists. All of the elements are arranged in the periodic table, which organizes the ... More »

Hydrogen does not exist in pure form in nature and instead is produced from a primary energy source, such as fossil fuels, solar, geothermal and wind energy, or extracted from other elements such as oxygen. Hydrogen is f... More »

Aluminum comes from several sources; it rarely occurs in pure form in nature, and is most frequently found embedded in other minerals, primarily bauxite. Bauxite and aluminum bear many physical characteristics; bauxite i... More »

Arsenic is typically classified as a metalloid element and may be found in several mineral forms in nature. It is commonly dispersed in small amounts in soil, as well as in larger amounts in gold, copper, lead and zinc o... More »