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			{{More citations needed|date=March 2021}}
⚫	{{About|the chemical urania|the type of cake|cake|the falsified documents|Yellowcake forgery}}
			{{short description|Uranium concentrate powder}}
		⚫	{{About|the chemical urania|the type of cake|cake|the falsified documents leading to an event popularly referred to as the 'yellowcake scandal'|Niger uranium forgeries}}
			{{distinguish|yellow substance}}
	{{chembox		{{chembox
			| Watchedfields = changed
	| verifiedrevid = 451677392		| verifiedrevid = 455328748
	| Name = Yellowcake
	| ImageFile = Yellowcake.jpg		| Name = Yellowcake
			| ImageFile = Yellowcake.jpg
	| ImageSize = 250px		| ImageSize = 250px
	| OtherNames = urania		| OtherNames = urania
	| Section1 = {{Chembox Identifiers		|Section1={{Chembox Identifiers
	| CASNo = 1344-57-6		| CASNo = 1344-57-6
	| CASNo_Ref = {{cascite|correct|CAS}}		| CASNo_Ref = {{cascite|correct|CAS}}
			| UNII_Ref = {{fdacite|correct|FDA}}
⚫	}}
			| UNII = L70487KUZO
⚫	| Section2 = {{Chembox Properties
⚫	| Formula = variable, see text
⚫	| MolarMass =
	| Appearance = Brown or black granules
	| Density = 9.055 g/cm<sup>3</sup>, solid
⚫	| Solubility =
	| MeltingPt = 2878&nbsp;°C
⚫	| BoilingPt =4018 ]
	}}		}}
		⚫	|Section2={{Chembox Properties
		⚫	| Formula = variable, see text
		⚫	| MolarMass =
			| Appearance = Yellow granules (as Yellowcake); Brown or black granules (UO<sub>2</sub> and others)
		⚫	| Solubility =
			| MeltingPtC = 2880
		⚫	| BoilingPt =
		⚫	}}
	}}		}}
			]
	{{expert-verify|date=July 2011}}
		⚫	'''Yellowcake''' (also called '''urania''') is a type of ] ] concentrate obtained from ], in an intermediate step in the processing of ]. It is a step in the processing of uranium after it has been mined but before fuel fabrication or ]. Yellowcake concentrates are prepared by various extraction and refining methods, depending on the types of ores. Typically, yellowcakes are obtained through the milling and chemical processing of uranium ], forming a coarse powder that has a pungent odor, is insoluble in water, and contains about 80% ], which melts at approximately 2880&nbsp;°C.
			==Overview==
⚫	'''Yellowcake''' (also called '''urania''') is a kind of ] concentrate ] obtained from ], in an intermediate step in the processing of ]. <ref></ref> Yellowcake concentrates are prepared by various extraction and refining methods, depending on the types of ores. Typically, yellowcakes are obtained through the milling and chemical processing of uranium ] forming a coarse powder which has a pungent odour, is insoluble in water and contains about 80% uranium oxide, which melts at approximately 2878&nbsp;°C. Although uranium is one of the densest metals on Earth, yellowcake is relatively light, with a density approximately that of elemental ].
		⚫	Originally, raw uranium ore was extracted by traditional mining, and this is still the case in many mines. It is first crushed to a fine powder by ] to produce "pulped" ore. This is further processed with concentrated ], ], or ] solutions to leach out the uranium. However, nearly half of yellowcake production is now produced by ]ing in which the solution is pumped through the uranium deposit without disturbing the ground.<ref name=Gil/> Yellowcake is what remains after drying and filtering. The yellowcake produced by most modern mills is actually brown or black, not yellow; the name comes from the color and texture of the concentrates produced by early mining operations.<ref>
			{{cite web|title=Yellowcake|url=https://www.nrc.gov/reading-rm/basic-ref/glossary/yellowcake.html|work=U.S. Nuclear Regulatory Commission|access-date=12 April 2014}}
			</ref><ref>{{cite web|title=Yellowcake|url=https://www.euronuclear.org/info/encyclopedia/y/yellow-cake.htm|work=European Nuclear Society nuclear glossary|access-date=10 July 2017|archive-date=6 July 2017|archive-url=https://web.archive.org/web/20170706110632/http://euronuclear.org/info/encyclopedia/y/yellow-cake.htm|url-status=dead}}</ref>
			] (U<sub>3</sub>O<sub>8</sub>) production, 1950–2021]]
⚫	The ore is first crushed to a fine powder by passing raw uranium ore through crushers and grinders to produce "pulped" ore. This is further processed with concentrated ], ], or ] solutions to leach out the uranium. Yellowcake is what remains after drying and filtering. The yellowcake produced by most modern mills is actually brown or black, not yellow; the name comes from the color and texture of the concentrates produced by early mining operations.
		⚫	Initially, the compounds formed in yellowcakes were not identified; in 1970, the ] still referred to yellowcakes as the final precipitate formed in the milling process and considered it to be ] or ]. The compositions were variable and depended upon the leachant and subsequent precipitating conditions. The compounds identified in yellowcakes include ], ], ], and ], along with various ]s. Modern yellowcake typically contains 70% to 90% ] (U<sub>3</sub>O<sub>8</sub>) by weight. Other oxides such as ] (UO<sub>2</sub>) and ] (UO<sub>3</sub>) exist.<ref>{{cite journal |year=1998 |title=Characterizing and Classifying Uranium Yellow Cakes: A Background |first=Donald M. |last=Hausen |journal=] |volume=50 |issue=12 |pages=45–47 |doi=10.1007/s11837-998-0307-5 |bibcode = 1998JOM....50l..45H |s2cid=97023067 }}</ref>
			Yellowcake is produced by all countries in which uranium ore is mined.<ref name=Gil>Gil, Laura (2018), , IAEA Bulletin (Online), vol. 59, iss, 2, pp. 22-23.</ref>
⚫	Initially, the compounds formed in yellowcakes were not identified; in 1970, the ] still referred to yellowcakes as the final precipitate formed in the milling process and considered it to be ] or ]. The compositions were variable and depended upon the leachant and subsequent precipitating conditions. Among the compounds identified in yellowcakes include: ], ], ], and ], along with various ]s. Modern yellowcake typically contains 70 to 90 percent ] (U<sub>3</sub>O<sub>8</sub>) by weight. Other oxides such as ] (UO<sub>2</sub>) and ] (UO<sub>3</sub>) exist.<ref>{{cite journal |year=1998 |title=Characterizing and Classifying Uranium Yellow Cakes: A Background |first=Donald M. |last=Hausen |journal=] |volume=50 |issue=12 |pages=45–47 |doi=10.1007/s11837-998-0307-5 |bibcode = 1998JOM....50l..45H }}</ref>
			=== Further processing ===
	]
	Yellowcake is used in the preparation of uranium fuel for ]s, for which it is smelted into purified UO<sub>2</sub> for use in ] for ] and other systems that use natural ].		Yellowcake is used in the preparation of uranium fuel for ]s, for which it is smelted into purified UO<sub>2</sub> for use in ] for ] and other systems that use natural ].
	Purified uranium metal (not the uranium oxide) can also be ]. In this process, the uranium is combined with ] to form ] gas (UF<sub>6</sub>). Next, that undergoes ] through the process of ], or in a ]. This can produce ] containing up to 20 percent U-235 that is suitable for use in most large civilian electric-power reactors (some nuclear power reactor designs such as ] heavy water reactors use natural uranium oxides with <1% U-235 as fuel). With further processing one obtains ], containing 20% or more U-235, that is suitable for use in compact nuclear reactors—usually used to power naval warships and ]s. Further processing can yield ] uranium with U-235 levels usually above 90%, suitable for ]s. However, since the collapse of the ], there is a worldwide surplus of highly-enriched uranium, and ].		Purified uranium can also be ]. In this process, the uranium oxides are combined with ] to form ] gas (UF<sub>6</sub>). Next, the gas undergoes ] through the process of ], or in a ]. This can produce ] containing up to 20% U-235 that is suitable for use in most large civilian electric-power reactors. With further processing, one obtains ], containing 20% or more U-235, that is suitable for use in compact nuclear reactors—usually used to power naval warships and ]s. Further processing can yield ] uranium with U-235 levels usually above 90%, suitable for ]s.
			== Radioactivity and safety ==
	Yellowcake is produced by all countries in which uranium ore is mined.
			]
			The uranium in yellowcake is almost exclusively (>99%) ], with very low radioactivity. U-238 has a ] of 4.468 billion years and emits radiation at a slow rate. This stage of processing is before the more radioactive U-235 is concentrated, so by definition, this stage of uranium has the same radioactivity as it did in nature when it was underground, as the proportions of isotopes are at their native relative concentration. Yellowcake is hazardous when inhaled.<ref>{{cite book |last1=Keith |first1=Sam |last2=Faroon |first2=Obaid |last3=Roney |first3=Nickolette |last4=Scinicariello |first4=Franco |last5=Wilbur |first5=Sharon |last6=Ingerman |first6=Lisa |last7=Llados |first7=Fernando |last8=Plewak |first8=Daneil |last9=Wohlers |first9=David |last10=Diamond |first10=Gary |title=Health Effects|url=https://www.ncbi.nlm.nih.gov/books/NBK158798/ |publisher=Agency for Toxic Substances and Disease Registry (US) |access-date=22 August 2021 |language=en |date=February 2013}}</ref>
	==See also==		==See also==
	*]		*]
	*]		*]
			*], an ore that is mostly ] (UO<sub>2</sub>)
	*]
	*]		*], fraudulently depicted Saddam Hussein trying to buy uranium powder
	*]		*], an American company involved in yellowcake processing
			*], a ] uranium mining and processing company
			*], a Niger uranium mining and processing company
			*], hydrous precipitates of which are known as "redcake"
	==References==		==References==
	{{reflist}}		{{reflist}}
			{{Uranium compounds}}
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