Calcium iodate is any of two inorganic compounds with the formula Ca(IO₃)₂(H₂O)_x, where x = 0 or 1. Both are colourless salts that occur as the minerals lautarite and bruggenite, respectively. A third mineral form of calcium iodate is dietzeite, a salt containing chromate with the formula Ca₂(IO₃)₂CrO₄.^[1] These minerals are the most common compounds containing iodate.

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Calcium iodate

Names
IUPAC name Calcium diiodate
Other names Lautarite
Identifiers
CAS Number	7789-80-2 (anhydrous) Y 10031-33-1 (hexahydrate) N
3D model (JSmol)	Interactive image
ChemSpider	23021 Y
ECHA InfoCard	100.029.265
EC Number	232-191-3
E number	E916 (glazing agents, ...)
PubChem CID	24619
UNII	L8MN4Y57BR (anhydrous) Y
CompTox Dashboard (EPA)	DTXSID40960972
InChI InChI=1S/Ca.2HIO3/c;2*2-1(3)4/h;2*(H,2,3,4)/q+2;;/p-2 Y Key: UHWJJLGTKIWIJO-UHFFFAOYSA-L Y InChI=1/Ca.2HIO3/c;2*2-1(3)4/h;2*(H,2,3,4)/q+2;;/p-2 Key: UHWJJLGTKIWIJO-NUQVWONBAT
SMILES [Ca+2].[O-]I(=O)=O.[O-]I(=O)=O
Properties
Chemical formula	Ca(IO3)2
Molar mass	389.88 g/mol (anhydrous) 407.90 g/mol (monohydrate)
Appearance	white solid
Density	4.519 g/cm3 (monohydrate)
Melting point	540 °C (1,004 °F; 813 K) (monohydrate)
Boiling point	decomposes
Solubility in water	0.09 g/100 mL (0 °C) 0.24 g/100 mL (20 °C) 0.67 g/100 mL (90 °C)
Solubility product (Ksp)	6.47×10−6
Solubility	soluble in nitric acid insoluble in alcohol
Magnetic susceptibility (χ)	-101.4·10−6 cm3/mol
Structure
Crystal structure	monoclinic (anhydrous) cubic (monohydrate) orthorhombic (hexahydrate)
Hazards
Flash point	non-flammable
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

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Lautarite, described as the most important mineral source of iodine, is mined in the Atacama Desert.^[1] Processing of the ore entails reduction of its aqueous extracts with sodium bisulfite to give sodium iodide. This comproportionation reaction is a major source of the sodium iodide.^[1]

Calcium iodate can be produced by the anodic oxidation of calcium iodide or by passing chlorine into a hot solution of lime in which iodine has been dissolved.

Calcium iodate is used as an iodine supplement in chicken feed.^[1] Ethylenediamine dihydroiodide (EDDI) is a more typical source of nutritional iodine.