The mineralogy of Iodine
| General Properties | |
|---|---|
| Symbol: | I |
| Atomic Number: | 53 |
| Standard atomic weight (Ar): | 126.90447(3) |
| Electron configuration: | [Kr] 4d10 5s2 5p5 |
| Photos | ||
|---|---|---|
     
|
||
| < |
Pure crystalline iodine
|
> |
| Atomic Properties | |
|---|---|
| Electronegativity (Pauling scale): | 2.66 |
| Atomic Radius: | 115 pm |
| Ionic Radius: | 220 pm (-1) |
| Van der Waals Radius: | 198 pm |
| 1st Ionization energy: | 1008 kJ/mol |
| 1st Electron affinity: | -295 kJ/mol |
| Oxidation States: | -1,1,3,5,7 |
| Physical Properties | |
|---|---|
| Standard State: | solid |
| Bonding Type: | covalent network |
| Melting Point: | 387 K |
| Boiling Point: | 457 K |
| Density: | 4.94 g/cm3 |
| Metal/Non-Metal: | halogen |
| Main isotopes of Iodine | ||||
|---|---|---|---|---|
| Isotope | % in Nature | Half Life | Decay type | Decay product |
| 123I | synthetic | 13h | ε | 123Te |
| 124I | synthetic | 4.176d | ε | 124Te |
| 125I | synthetic | 59.40d | ε | 125Te |
| 127I | 100% | - | Spontaneous fission ? | |
| 129I | trace | 1.57×107y | β− | 129Xe |
| 131I | synthetic | 8.02070d | β− | 131Xe |
| 135I | synthetic | 6.57h | β− | 135Xe |
| Main ions of Iodine | ||||
|---|---|---|---|---|
| Name | Ion | Example minerals | ||
| iodide | I- | Iodargyrite, Marshite | ||
| hypoiodide | IO- | |||
| iodite | [IO2]- | |||
| iodate | [IO3]- | Bellingerite, Lautarite, Salesite | ||
| periodate | [IO4]- | |||
| periodate | [IO6]5- | |||
| Other Information | |
|---|---|
| Year Discovered: | 1811 |
| Discovered By: |
Bernard Courtois
|
| Year Isolated: | 1811 |
| Isolated By: | Bernard Courtois |
| Named For: | Greek: ioeides - violet or purple |
| CPK color coding: | #940094 |
| External Links: | WikipediaWebElementsLos Alamos National LaboratoryTheodore Gray's PeriodicTable.com |
| Simple Compounds | |||
|---|---|---|---|
| Fluorides | iodine fluoride | IF | +1 |
| iodine trifluoride | IF3 | +3 | |
| iodine pentafluoride | IF5 | +5 | |
| iodine heptafluoride | IF7 | +7 | |
| Chlorides | iodine chloride | ICl | +1 |
| diiodine hexachloride | [ICl3]2 | +3 | |
| Oxides | diiodine pentaoxide | I2O5 | +5 |
| diiodine tetraoxide | I2O4 | +4 | |
| tetraiodine nonaoxide | I4O9 | ||
| Mineral Diversity of Iodine | |
|---|---|
| 2. Sulfides And Sulfosalts | 5 valid mineral species |
| 3. Halides | 12 valid mineral species |
| 4. Oxides | 10 valid mineral species |
| 7. Sulfates | 3 valid mineral species |
| Total: | 30 valid species containing essential Iodine |
| Geochemistry of Iodine | |
|---|---|
| Goldschmidt classification: | Lithophile |
| I- is essential to nutrition of at least some vertebrates ('essential minerals'). | |
| I- forms minerals with Cu+. | |
| I- forms minerals with Ag+. | |
| Elemental Abundance for Iodine | ||
|---|---|---|
| Crust (CRC Handbook) | 4.5 x 10-7 | mass fraction, kg/kg |
| Crust (Kaye & Laby) | 5 x 10-7 | mass fraction, kg/kg |
| Crust (Greenwood) | 4.6 x 10-7 | mass fraction, kg/kg |
| Crust (Ahrens/Wänke) | 1.540 x 10-6 | mass fraction, kg/kg |
| Sea Water (CRC Handbook) | 6 x 10-8 | mass per volume fraction, kg/L |
| Sea Water (Kaye & Laby) | 6.4 x 10-8 | mass per volume fraction, kg/L |
| Solar System (Kaye & Laby) | 9.0 x 10-7 | atom mole fraction relative to Si=1 |
| Solar System (Ahrens) | 9.00 x 10-7 (21%) | atom mole fraction relative to Si=1 (% uncertainty) |
| Element association of Iodine in the Mineral World | |||
|---|---|---|---|
| This table compares the known valid mineral species listed listed with Iodine and the other elements listed based on the official IMA formula. Note that unlike other sections on this page this includes non-essential elements. The first data column contains the total number of minerals listed with Iodine and the element listed for that row. The second data column lists this number as a percentage of all minerals listed with Iodine. The final data column compares this percentage against the percentage of all minerals that contain the element listed in each row. Click on a heading to sort. |
| Periodic Table | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Tellurium << Iodine >> Xenon | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Most widespread minerals containing Iodine |
|---|
| This list of minerals containing Iodine is built from the mindat.org locality database. This is based on the number of localities entered for mineral species and is therefore slanted towards minerals interesting to collectors with less coverage of common rock-forming-minerals so it does not give an undistorted distribution of Iodine mineral species. It is more useful when comparing rare species rather than common species. |
| Name | Formula | Crystal System | Mindat Localities |
|---|---|---|---|
| Iodargyrite | AgI | Hexagonal | 224 |
| Perroudite | Hg5Ag4S5(I,Br)2Cl2 | Orthorhombic | 27 |
| Schwartzembergite | Pb5H2(IO2)O4Cl3 | Tetragonal | 21 |
| Marshite | CuI | Isometric | 18 |
| Seeligerite | Pb3(IO3)OCl3 | Orthorhombic | 14 |
| Miersite | (Ag,Cu)I | Isometric | 14 |
| Dietzeite | Ca2(IO3)2(CrO4) · H2O | Monoclinic | 6 |
| Hectorfloresite | Na9(SO4)4(IO3) | Monoclinic | 5 |
| Tocornalite | (Ag,Hg)I | Hexagonal | 4 |
| Fuenzalidaite | K6(Na,K)4Na6Mg10(SO4)12(IO3)12 · 12H2O | Trigonal | 4 |
| Photos |
|---|
| Localities with greatest number of different Iodine mineral species |
|---|
Spotted a mistake/omission? - These pages are a work in progress, so please send all comments/corrections to jolyon@mindat.org. Thank you.
Constants and physical property data from:
David R. Lide (ed.), CRC Handbook of Chemistry and Physics, 85th Edition. CRC Press. Boca Raton, Florida (2005).
Kaye and Laby Tables of Physical & Chemical Constants (2005). Section 3.1.3, Abundances of the elements
A. Earnshaw, N. Greenwood, Chemistry of the Elements, 2nd edition, Butterworth-Heinemann, (1997)
Thomas J. Ahrens (ed.), Global Earth Physics : A Handbook of Physical Constants, American Geophysical Union (1995)
L.B. Railsback, An Earth Scientist's Periodic Table of the Elements and Their Ions : Geology 31:9 p737-740 (2003)
Emsley, J. Nature's Building Blocks: An A-Z Guide to the Elements. New York: Oxford University Press (2001)
