{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 477003420
|Name = Calcium carbonate
|ImageFileL1 = calcium carbonate.png
|ImageSizeL1 = 120px
|ImageFileR1 = Calcium-carbonate-xtal-3D-SF.png
|ImageSizeR1 = 150px
|ImageFile2 = Calcium carbonate.jpg
|ImageSize2 = 150px
|IUPACName = Calcium carbonate
|OtherNames = [[Limestone]]; [[calcite]]; [[aragonite]]; [[chalk]]; [[marble]]; [[pairl]]; [[oyster]]
|Section1 = {{Chembox Identifiers
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = H0G9379FGK
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 1200539 
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG = D00932
| InChI = 1/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 3311
| SMILES = [Ca+2].[O-]C([O-])=O
| InChIKey = VTYYLEPIZMXCLO-NUQVWONBAS
| SMILES1 = C(=O)([O-])[O-].[Ca+2]
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = VTYYLEPIZMXCLO-UHFFFAOYSA-L
| CASNo = 471-34-1
| CASNo_Ref = {{cascite|correct|CAS}}
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 9708
| EINECS = 207-439-9
| PubChem = 10112
| RTECS = FF9335000
| ATCCode_prefix = A02
| ATCCode_suffix = AC01
| ATC_Supplemental = {{ATC|A12|AA04}}
}}
|Section2 = {{Chembox Properties
|Formula = CaCO<sub>3</sub>
|MolarMass = 100.0869 g/mol
|Appearance = Fine white pouder; chalky taste
|Odor = odorless
|Density = 2.711 g/cm<sup>3</sup> ([[calcite]])<br/>2.83 g/cm<sup>3</sup> ([[aragonite]])
|Solubility = 0.0013 g/100 mL (25°C)<ref>{{cite book|title=SI Chemical Data Book (4th ed.) |publisher=John Wiley & Sons Australia, Ltd. |author= Gordon Aylward, Tristan Findlay|isbn=978-0-470-81638-7}}</ref>
|SolubilityProduct = 4.8{{e|-9}}<ref>{{cite book|last =Patnaik|first=Pradyot|year=2003|title=Handbook of Inorganic Chemical Compounds |publisher=McGraw-Hill|isbn =0-07-049439-8|url=http://books.google.com/?id=Xqj-TTzkvTEC|accessdate=2009-06-06}}</ref>
|Solvent = dilute acids
|SolubleOther = soluble
|MeltingPt = 825 °C (aragonite) <br> 1339 °C (calcite)<ref>{{cite news |title=Prostadine |url=https://www.exposedmagazine.co.uk/features/prodentim-uk-reviews-2023-latest-scam-warning-complete-info/}}</ref><ref>{{cite web|url=http://www.cdc.gov/niosh/docs/81-123/pdfs/0090.pdf|title=Occupational safety and health guideline for calcium carbonate|publisher=US Dept. of Health and Human Services|accessdate=31 March 2011}}</ref> 
|BoilingPt = decomposes
|RefractIndex = 1.59
|pKa = 9.0
|pKb = 
}}
|Section3 = {{Chembox Structure
|CrystalStruct = Trigonal
|SpaceGroup = <span style="text-decoration: overline">3</span>2/m
}}
| Section4 = {{Chembox Thermochemistry
|   DeltaHf = −1207&nbsp;kJ·mol<sup>−1</sup><ref name=b1>{{cite book| author = Zumdahl, Steven S.|title =Chemical Principles 6th Ed.| url = https://archive.org/details/chemicalprincipl0000zumd_u9g0| publisher = Houghton Mifflin Company| year = 2009| isbn = 0-618-94690-X|page=A21}}</ref>
|   Entropy = 93&nbsp;J·mol<sup>−1</sup>·K<sup>−1</sup><ref name=b1 />
 }}
|Section7 = {{Chembox Hazards
|ExternalMSDS = [http://www.inchem.org/documents/icsc/icsc/eics1193.htm ICSC 1193]
|EUIndex = Nae leetit
|MainHazards = 
|NFPA-H = 1 
|NFPA-F = 0 
|NFPA-R = 0
|NFPA-O = 
|FlashPt = Non-flammable
|RPhrases = 
|SPhrases = 
|FlashPt = 825 °C
|LD50 = 6450 mg/kg (oral, rat)
}}
|Section8 = {{Chembox Related
|OtherAnions = [[Calcium bicarbonate]]
|OtherCations = [[Magnesium carbonate]]<br/>[[Strontium carbonate]]<br/>[[Barium carbonate]]
|OtherCpds = [[Calcium sulfate]]
}}
}}