Editing API gravity (section)

==Classifications or grades==
[[File:Lower 48 U.S. states production of crude oil by API gravity in January 2015 through July 2019 (48880018261).png|thumb|upright=1.4|API gravity of crude oil produced in the [[contiguous United States]]]]
Generally speaking, oil with an API gravity between 40 and 45° commands the highest prices. Above 45°, the molecular chains become shorter and less valuable to refineries.<ref>{{cite web|title=Comments on Crude Oil Gravity Adjustments |url=http://dnr.louisiana.gov/sec/execdiv/techasmt/oil_gas/crude_oil_gravity/comments_1989.htm |archive-url=https://web.archive.org/web/20060502160519/http://dnr.louisiana.gov/sec/execdiv/techasmt/oil_gas/crude_oil_gravity/comments_1989.htm |url-status=dead |archive-date=2 May 2006 |publisher=Louisiana Department of Natural Resources |access-date=6 January 2014 }}</ref>

[[Crude oil]] is classified as light, medium, or heavy according to its measured API gravity.

* [[Light crude oil]] has an API gravity higher than 31.1° (i.e., less than 870&nbsp;kg/m<sup>3</sup>)
* Medium oil has an API gravity between 22.3 and 31.1° (i.e., 870 to 920&nbsp;kg/m<sup>3</sup>)
* [[Heavy crude oil]] has an API gravity below 22.3° (i.e., 920 to 1000&nbsp;kg/m<sup>3</sup>)
* Extra heavy oil has an API gravity below 10.0° (i.e., greater than 1000&nbsp;kg/m<sup>3</sup>)

However, not all parties use the same grading.<ref>Crude oil grades, Crudemonitor.ca, web PDF file: [http://www.crudemonitor.ca/quickfacts/misc/grades.pdf CMonitor-Gr-PDF] {{webarchive |url=https://web.archive.org/web/20071008191730/http://www.crudemonitor.ca/quickfacts/misc/grades.pdf |date=October 8, 2007 }}</ref> The [[United States Geological Survey]] uses slightly different ranges.<ref>USGS FS2006-3133_508, web PDF file: [http://pubs.usgs.gov/fs/2006/3133/pdf/FS2006-3133_508.pdf USGS-508-PDF]</ref>

Crude oil with API gravity less than 10° is referred to as [[extra heavy oil]] or [[bitumen]]. Bitumen derived from [[oil sands]] deposits in Alberta, Canada, has an API gravity of around 8°. It can be diluted with lighter hydrocarbons to produce [[diluted bitumen]], which has an API gravity of less than 22.3°, or further "upgraded" to an API gravity of 31 to 33° as [[synthetic crude]].<ref>Canadian Centre for Energy Information. [http://www.centreforenergy.com/AboutEnergy/ONG/Oil/Overview.asp?page=2 "What is crude oil?"] {{Webarchive|url=https://web.archive.org/web/20140710020428/http://www.centreforenergy.com/AboutEnergy/ONG/Oil/Overview.asp?page=2 |date=2014-07-10 }}. Retrieved on: 2012-09-10.</ref>