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	{{chembox		{{chembox
			| Watchedfields = changed
	| verifiedrevid = 401296863
			| verifiedrevid = 438439590
	| ImageFile =
			| ImageFile = Basic lead carbonate.svg
	| ImageSize =
	| IUPACName =		| ImageSize =
			| IUPACName =
	| OtherNames = basic lead carbonate
			| OtherNames = Basic lead carbonate
	| Section1 = {{Chembox Identifiers
			| Section1 = {{Chembox Identifiers
	| CASNo_Ref = {{cascite}}
			| CASNo_Ref = {{cascite|correct|CAS}}
	| CASNo = 1319-46-6		| CASNo = 1319-46-6
	| PubChem =		| ChemSpiderID = 14148
	| SMILES =		| EINECS = 215-290-6
			| UNII_Ref = {{fdacite|correct|FDA}}
			| UNII = WDF96425HV
			| PubChem = 14834
			| StdInChI=1S/2CH2O3.2H2O.3Pb/c2*2-1(3)4;;;;;/h2*(H2,2,3,4);2*1H2;;;/q;;;;3*+2/p-6
			| StdInChIKey = RYZCLUQMCYZBJQ-UHFFFAOYSA-H
			| SMILES = C(=O)().C(=O)().....
			}}
			| Section2 = {{Chembox Properties
			| Formula = 2PbCO<sub>3</sub>·Pb(OH)<sub>2</sub>
			| MolarMass = 775.633 g/mol
			| Appearance = White powder
			| Density =
			| MeltingPt =
			| BoilingPt =
			| Solubility =
	}}		}}
	| Section2 = {{Chembox Properties		| Section3 = {{Chembox Hazards
			| MainHazards = Lead poisoning
	| Formula = (PbCO<sub>3</sub>)<sub>2</sub>·Pb(OH)<sub>2</sub>
			| GHSPictograms = {{GHS07}}{{GHS08}}{{GHS09}}
	| MolarMass = 775.633 g/mol
			| GHSSignalWord =
	| Appearance = white powder
			| HPhrases = {{H-phrases|302|332|360|373|410}}
	| Density =
			| PPhrases = {{P-phrases|201|202|260|261|264|270|271|273|281|301+312|304+312|304+340|308+313|312|314|330|391|405|501}}
	| MeltingPt =
	| BoilingPt =		| FlashPt =
	| Solubility =		| AutoignitionPt =
	}}
	| Section3 = {{Chembox Hazards
	| MainHazards = lead poisoning
	| FlashPt =
	| Autoignition =
	}}		}}
	}}		}}
	], with white lead second left, bottom shelf.]]		], with white lead second from left, bottom shelf]]
	'''White lead''' is the chemical compound (PbCO<sub>3</sub>)<sub>2</sub>·Pb(OH)<sub>2</sub>.<ref name="Wiberg">''Inorganic Chemistry'',Egon Wiberg, Arnold Frederick Holleman Elsevier 2001 ISBN 0123526515</ref> It was formerly used as an ingredient for ] and a cosmetic called ], because its ] quality made it a good ]. However, it tended to cause ], and its use has been banned in most countries.		'''White lead''' is the basic lead carbonate 2PbCO<sub>3</sub>·Pb(OH)<sub>2</sub>.<ref name="Wiberg">{{cite book|title=Inorganic Chemistry |author1-first=Egon |author1-last=Wiberg |author2-first=Arnold Frederick |author2-last=Holleman |publisher=Elsevier |year=2001 |isbn=0-12-352651-5}}</ref> It is a complex ], containing both carbonate and hydroxide ions. White lead occurs naturally as a mineral, in which context it is known as '''hydrocerussite''',<ref name="Wiberg"/> a ] of ].<ref>''see'' ]</ref> It was formerly used as an ingredient for ] and a cosmetic called ], because of its ] and the satiny smooth mixture it made with dryable oils. However, it tended to cause ], and its use has been banned in most countries.<ref>{{cite journal |url=http://rachel.org/files/document/Lead_Poisoning_in_Historical_Perspective.pdf |last=Hernberg |first=Sven |title=Lead Poisoning in a Historical Perspective |journal=American Journal of Industrial Medicine |volume=38 |issue=3 |pages=244–254 |date=September 2000 |doi=10.1002/1097-0274(200009)38:3<244::AID-AJIM3>3.0.CO;2-F |pmid=10940962 |citeseerx=10.1.1.477.2081 |access-date=2015-04-12 |archive-date=2013-04-13 |archive-url=https://web.archive.org/web/20130413014235/http://rachel.org/files/document/Lead_Poisoning_in_Historical_Perspective.pdf |url-status=dead }}</ref>
			Basic lead carbonate is produced by treating lead acetate with ] and air.<ref name=Ullmann>{{Ullmann|first=Dodd S.|last=Carr|year=2005|title=Lead Compounds|doi=10.1002/14356007.a15_249}}</ref> In the laboratory procedure treats lead acetate with ].<ref>{{cite book|author=M. Baudler|chapter=Neutral and Basic Lead Carbonate|title=Handbook of Preparative Inorganic Chemistry, 2nd Ed. |editor=G. Brauer|publisher=Academic Press|year=1963|place=NY,NY|volume=2pages=766}}</ref> It occurs naturally as the mineral ].<ref>''Inorganic Chemistry'', Egon Wiberg, Arnold Frederick Holleman Elsevier 2001 {{ISBN|0-12-352651-5}}</ref> The compound has been characterized by ], which confirms the formula. The structure is complicated, features two kinds of Pb(II) sites, those bonded to hydroxide and those bonded to carbonate and hydroxide.<ref name=XRD/>
	White lead has been the principal white of classical European ].<ref name="naturalpigments" >{{cite web
	|title=Stack Process White Lead (Old Dutch Method)
	|url=http://naturalpigments.com/detail.asp?PRODUCT_ID=475-11S
	}} Commercial supplier, offering original pigments to the conservation and reproduction markets</ref> There have been claims that it is partly responsible for darkening of old paintings over time, reacting with trace amounts of ] in the air to produce black ]. Other authorities dispute this; the most traditional view is that impermanent pigments and dirty varnish (which is often cleanable) are more likely responsible for darkening.
			==Related white lead compounds==
	Paintings and the role of varnish, which might protect the white lead yet itself darken, aside-- according to Michelle Facini, a paper conservator at the National Gallery of Art, lead carbonate to lead sulfide is indeed what happens to some lead chalks/paints in drawings and watercolors and other works done on paper and unvarnished. Varnish is meant to be removable from an oil painting, to strip off when it dirties or cracks; but on paper it soaks through and becomes inseparable from the paper fibers, ruinous as it ages. This is why works on paper are never, or should never, be varnished. Thus far more frequently for paper works than for paintings, lead white was exposed directly to sulphur in the air (particularly from unfiltered coal say in 19th ce industrial London, for example) to turn to the black sulfide.
			White lead compounds known as ] were used as additive for lubricants for ] and in machine shops.<ref>{{cite book|last=Klemgard|first=E.N.|chapter=Lead base greases|title=Lubricating Greases Their Manufacture And Use|year=1937|publisher=Reinhold Publishing Corporation|pages=677|url=https://archive.org/details/in.ernet.dli.2015.84129}}</ref> Lead soap was also used as an ] for paints made with ] or air drying paints made with ]s. Lead is often used with cobalt driers. Lead free substitutes have been developed to replace this use of lead in paint.
			A second basic lead carbonate is known with the formula {{chem2|6Pb(CO3)*3Pb(OH)6*PbO}}.<ref name=XRD>{{cite journal |doi=10.1107/S0108270102006844 |title=Synthetic hydrocerussite, 2PbCO<sub>3</sub>·Pb(OH)<sub>2</sub>, by X-ray powder diffraction |date=2002 |last1=Martinetto |first1=Pauline |last2=Anne |first2=Michel |last3=Dooryhée |first3=Eric |last4=Walter |first4=Philippe |last5=Tsoucaris |first5=Georges |journal=Acta Crystallographica Section C Crystal Structure Communications |volume=58 |issue=6 |pages=i82–i84 |pmid=12050408 }}</ref>
	In any event, white lead has been mostly supplanted in artistic use by ], which is structurally weaker than white lead. Critics argue that many of these substitutes are much less permanent.<ref name="naturalpigments2" >{{cite web
	|title=Zinc White Problems in Oil Paint
	|url=http://naturalpigments.com/education/article.asp?ArticleID=127
	}} The Smithsonian's Museum Conservation Institute exposes long-term problems with zinc white</ref> White lead is less used by today's painters, not because of its toxicity directly; but simply because its toxicity in other contexts has led to trade restrictions that make lead white difficult for artists to obtain in sufficient quantities. ], the English paint company, was recently restricted from selling its flake white in tubes and now must sell exclusively in 150mL tins, even as in the US, dutch-method flake white becomes increasingly popular as traditionalists, fascinated with the pigments of old, seek them out.
			==History==
	Historically, white lead was produced by the Dutch process. This involved casting metallic ] as thin buckles. These were corroded with acetic acid in the presence of ]. This was done by placing them over pots with a little ] (containing ]). These were stacked up and covered with a mixture of decaying dung and spent tanner's bark, which supplied the CO2 and left for six to fourteen weeks, by which time the blue-grey lead had corroded to white lead. The pots were then taken to a separating table where scraping and pounding removed the white lead from the buckles. The powder was then dried and packed for shipment.<ref> based on Warren, Christian. 'Toxic Purity: The progressive era origins of America’s lead paint poisoning epidemic'. ''Business History Review''. Winter 1999, Vol. 73(4)</ref>. One happy finding was that it was not necessary to dry the paste of white lead in water. All that needed was to mill the paste with linseed oil, when the white lead would take up the oil and reject the water,to give white lead in oil.
			What is commonly known today as the "Dutch method" for the preparation of white lead was described as early as ]<ref>], '']'' (1937)</ref> (ca. 300 BC), in his brief work on rocks or minerals, ] or ''History of Stones.'' His directions for the process were repeated throughout history by many authors of chemical and ] literature. The uses of cerussa were described as an external medication and pigment.<ref>{{cite book|last=Stillman|first=John Maxson|title=The Story of Early Chemistry|url=https://archive.org/details/in.ernet.dli.2015.179875|year=1924|publisher=D. Appleton|pages=–20}}</ref>
			Clifford Dyer Holley quotes from Theophrastus' ''History of Stones''<ref>Theophrastus, ''History of Stones'', p.223</ref> as follows, in his book ''The Lead and Zinc Pigments''.
	In the eighteenth century, white lead paints were routinely used to repaint the hulls and floors of ] vessels, to waterpoof the timbers and limit infestation by ] worms.<ref>{{cite book |title =Captain James Cook | first =Richard | last =Hough | coauthors= | month = | year =1994 | publisher =Hodder and Stoughton | page =56 | url = | isbn =9780340825563}}</ref>
			{{blockquote|text=
			Lead is placed in earthen vessels over sharp vinegar, and after it has acquired some thickness of a sort of rust, which it commonly does in about ten days, they open the vessels and scrape it off, as it were, in a sort of foulness; they then place the lead over vinegar again, repeating over and over again the same method of scraping it till it has wholly dissolved. What has been scraped off they then beat to powder and boil for a long time, and what at last subsides to the bottom of the vessel is ceruse.<ref>{{cite book|last=Holley|first=Clifford Dyer|title=The Lead and Zinc Pigments|url=https://archive.org/details/dli.bengal.10689.2347|year=1909|publisher=John Wiley & Sons|page=}}</ref>
			}}
			Later descriptions of the Dutch process involved casting metallic ] as thin buckles and corroded with ] in the presence of ]. This was done by placing them over pots with a little ] (which contains acetic acid). These were stacked up and covered with a mixture of decaying dung and spent ], which supplied the CO<sub>2</sub>, and left for six to fourteen weeks, by which time the blue-grey lead had corroded to white lead. The pots were then taken to a separating table where scraping and pounding removed the white lead from the buckles. The powder was then dried and packed for shipment or shipped as a paste.<ref> {{Webarchive|url=https://web.archive.org/web/20080403001351/http://www.lead411.org/Templates/history/white_lead_pigment.htm |date=2008-04-03 }} based on Warren, Christian. "Toxic Purity: The progressive era origins of America’s lead paint poisoning epidemic". ''Business History Review''. Winter 1999, Vol. 73(4)</ref> One benefit of the process was that it was not necessary to dry the paste of white lead, removing its water. All that needed was to mill the paste with ], and the white lead would take up the oil and reject the residual water, to give white lead in oil. {{Citation needed|date=June 2013}}
	White lead compounds were also used as lubricants for ] and in machine shops, especially between work being turned in a ] and a ].
			==Paints==
	White lead occurs naturally as a mineral, in which context it is known as ].<ref name = "Wiberg"/>
			{{Main|Lead white}}
			]]]
			White lead has been mostly supplanted in artistic use by ], which has much higher tinting strength than white lead.<ref>{{cite book|last=Laver |first=M. |chapter=Titanium Dioxide Whites |editor-last=Fitzhugh |editor-first= E. W. |title=Artists' Pigments |volume=3 |publisher=Oxford University Press |year=1997 |page=309}}</ref> Critics argue that substitutes like zinc oxide and titanium dioxide are more reactive, become brittle, and can flake off.<ref name="naturalpigments2">{{cite web|title=Zinc White: Problems in Oil Paint |url=https://www.naturalpigments.com/artist-materials/zinc-white-oil-paint-color/}} The Smithsonian's Museum Conservation Institute exposes long-term problems with zinc white</ref><ref>{{cite journal |last1=Macchia |first1=Andrea |last2=Cesaro |first2=Stella |last3=Keheyan |first3=Yeghis |last4=Ruffolo |first4=Silvestro |last5=La Russa |first5=Mauro |title=White zinc in Linseed Oil Paintings: Chemical, Mechanical and Aesthetic Aspects |journal=Periodico di Mineralogia |date=2015 |volume=84 |issue=3A |pages=483–495 |doi=10.2451/2015PM0027}}</ref> White lead is less used by today's painters, not because of its toxicity directly; but simply because its toxicity in other contexts has led to trade restrictions that make white lead difficult for artists to obtain in sufficient quantities.<ref>{{cite journal |last1=Raine |first1=Craig |title=Epic of gossip (review of ''The Lives of Lucian Freud : Fame 1968-2011'' by William Feaver |journal=The Spectator |date=5 September 2020 |page=30/2}}</ref> ], the English paint company, was restricted in 2014 from selling its flake white in tubes and now must sell exclusively in {{cvt|150|ml}} tins.<ref>{{cite web |title=Choosing a white in oil colour |url=http://www.winsornewton.com/na/discover/tips-and-techniques/oil-colour/choosing-a-white-in-oil-colour-us |website=Winsor & Newton |access-date=18 October 2014 |quote="For reasons of toxicity these Lead White colours are only available in tins in the EU." |archive-date=8 October 2014 |archive-url=https://web.archive.org/web/20141008003654/http://www.winsornewton.com/na/discover/tips-and-techniques/oil-colour/choosing-a-white-in-oil-colour-us |url-status=dead }}</ref>
	==Other synonyms (as an art pigment)==
	], flake white, silver white, slate white, Berlin white, Cremnitz / Kremnitz white, Crems / Krems white, Nottingham white, Vienna white<ref name="naturalpigments" />
			In the eighteenth century, white lead paints were routinely used to repaint the hulls and floors of ] vessels, to waterproof the timbers and limit infestation by ].<ref>{{cite book|title=Captain James Cook |first=Richard |last=Hough |year=1994 |publisher=Hodder and Stoughton |page=56 |isbn=978-0-340-82556-3}}</ref>
			===Other synonyms (as an art pigment)===
			Among the synonyms for white lead are Berlin white, ] white, Dutch white lead, flake white, Flemish white, Krems white, London white, Pigment White 1, Roman white, silver white, slate white and Vienna white.<ref>{{cite web |title=Lead white |url=http://cameo.mfa.org/Lead_white |website=Conservation and Art Materials Encyclopedia Online (CAMEO) |publisher=Museum of Fine Arts, Boston (Massachusetts) |access-date=6 June 2019}}</ref>
	== See also ==		== See also ==
			* ]
			* ]
	* ]		* ]
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	{{Reflist}}		{{Reflist}}
			==Further reading==
	]
			* Gettens, R.J., Kühn, H. and Chase, W.T. "Lead White", in Roy, A., (Ed), ''Artists' Pigments'', Vol 2, Oxford University Press, 1993, pp.&nbsp;67–81
	]
	]
			==External links==
	]
			{{NSRW Poster|White Lead}}
	]
			* , Colourlex
	]
	]
			{{lead compounds}}
	]
			{{Authority control}}
	]
	]
			]
	]
			]
	]
			]