Editing Group 6 element (section)

==Occurrence and production==

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Chromium is a very common [[naturally occurring element]]. It is the [[Abundance of elements in Earth's crust|21st most abundant element]] in the Earth's crust with an average concentration of 100 ppm. The most common [[oxidation state]]s for chromium are zero, trivalent, and hexavalent states. Most naturally occurring chromium is in the [[hexavalent]] state.<ref>{{Cite journal |last=Barnhart |first=J. |date=August 1997 |title=Occurrences, uses, and properties of chromium |journal=Regulatory Toxicology and Pharmacology |volume=26 |issue=1 Pt 2 |pages=S3–7 |doi=10.1006/rtph.1997.1132 |issn=0273-2300 |pmid=9380835}}</ref> About two-fifths of the worlds chromium are produced in [[South Africa]], with [[Kazakhstan]], [[India]], [[Russia]], and [[Turkey]] following. Chromium is mined as chromite ore.

Molybdenum is refined mainly from [[molybdenite]]. It is mainly mined in the United States, China, Chile, and Peru, with the total amount produced being 200,000 tonnes per year.<ref>{{Cite web |title=Molybdenum - Element information, properties and uses {{!}} Periodic Table |url=https://www.rsc.org/periodic-table/element/42/molybdenum |access-date=2023-09-22 |website=www.rsc.org}}</ref>

Tungsten is not a common element on Earth, having an average concentration of 1.5 ppm in Earth's crust. Tungsten is mainly found in the minerals [[wolframite]] and [[scheelite]], and it usually never occurs as a free element in nature. The largest producers of tungsten in the world are China, Russia, and Portugal.

Seaborgium is a [[transuranium element]] that is made artificially by bombarding [[californium]]-249 with [[oxygen]]-18 nuclei. It is artificial, therefore it does not occur in nature.<ref>{{Cite web |title=Seaborgium - Element information, properties and uses {{!}} Periodic Table |url=https://www.rsc.org/periodic-table/element/106/seaborgium |access-date=2023-09-22 |website=www.rsc.org}}</ref>