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The mineralogy of Caesium

General Properties
Symbol:Cs
Commodity pages:Caesium
Other names:Also known as cesium, primarily in the United States.
Atomic Number:55
Standard atomic weight (Ar):132.9054519(2)
Electron configuration:[Xe] 6s1
Photos
<
Five different photos of the same vial with 1 gram of caesium
>
Atomic Properties
Electronegativity (Pauling scale):0.79
Atomic Radius:298 pm
Ionic Radius:167 pm (+1)
1st Ionization energy:376 kJ/mol
1st Electron affinity:-46 kJ/mol
Oxidation States:1
Physical Properties
Standard State:solid
Bonding Type:metallic
Melting Point:302 K
Boiling Point:944 K
Density:1.88 g/cm3
Metal/Non-Metal:alkali metal
Main isotopes of Caesium
Isotope% in NatureHalf LifeDecay typeDecay product
133Cs100%-Spontaneous fission ?
134Cssynthetic2.0648yε134Xe
β−134Ba
135Cstrace2.3×106yβ−135Ba
137Cstrace30.17yβ−137Ba
Main ions of Caesium
NameIonExample minerals
cesiumCs+londonite
Other Information
Year Discovered:1860
Discovered By:
07863350017362077371011.jpg
Robert Bunsen and Gustav Kirchhoff
Year Isolated:1882
Isolated By:
05305690017362077389337.jpg
Carl Setterberg
Named For:From Latin: caesius - "sky blue"
CPK color coding:#57178F
External Links:WikipediaWebElementsLos Alamos National LaboratoryTheodore Gray's PeriodicTable.com
Simple Compounds
Sulfidesdicaesium sulphideCs2S+1
dicaesium disulphideCs2S2+1
dicaesium trisulphideCs2S3+1
dicaesium hexasulphideCs2S6+1
dicaesium tetrasulphideCs2S4+1
dicaesium pentasulphideCs2S5+1
dicaesium heptasulphideCs2S7+1
Selenidesdicaesium selenideCs2Se+1
Telluridesdicaesium tellurideCs2Te+1
Hydridescaesium hydrideCsH+1
Fluoridescaesium fluorideCsF+1
Chloridescaesium chlorideCsCl+1
Iodidescaesium iodideCsI+1
Oxidesdicaesium oxideCs2O+1
caesium superoxideCsO2+1
dicaesium peroxideCs2O2+1
Caesium as a chromophore in minerals and gems
ChromophoreDescription
Cs+Does NOT cause colour as it has no electrons in d-orbitals. Minerals where Cs was previously thought to be a colouring agent probably contain other ions such as Mn#2+#.
Mineral Diversity of Caesium
2. Sulfides And Sulfosalts 2 valid mineral species
4. Oxides 3 valid mineral species
6. Borates2 valid mineral species
8. Phosphates, Arsenates, Vanadates3 valid mineral species
9. Silicates 17 valid mineral species
Total:27 valid species containing essential Caesium
Minerals with the greatest weight % of Caesium
KirchhoffiteCs(BSi2O6)44.92 %
Pollucite(Cs,Na)2(Al2Si4O12)·2H2O40.27 %
PautoviteCsFe2S339.00 %
Ramanite-(Cs)Cs[B5O6(OH)4]·2H2O34.34 %
Cesiokenopyrochlore◻Nb2(O,OH)6(Cs,◻) 32.05 %
SokolovaiteCsLi2Al(Si4O10)F227.45 %
NanpingiteCsAl2(AlSi3O10)(OH,F)227.01 %
GarmiteCsLiMg2(Si4O10)F226.65 %
GorbunoviteCsLi2(Ti,Fe)Si4O10(F,OH,O)226.32 %
KreiteriteCsLi2Fe3+(Si4O10)F225.91 %
Geochemistry of Caesium
Goldschmidt classification:Lithophile
Cs+ enters later phases in igneous rocks due to its large size.
Elemental Abundance for Caesium
Crust (CRC Handbook)3 x 10-6mass fraction, kg/kg
Crust (Kaye & Laby)1.6 x 10-6mass fraction, kg/kg
Crust (Greenwood)2.6 x 10-6mass fraction, kg/kg
Crust (Ahrens/Taylor)1.000 x 10-6mass fraction, kg/kg
Crust (Ahrens/Wänke)1.310 x 10-6mass fraction, kg/kg
Upper Crust (Ahrens/Taylor)3.700 x 10-6mass fraction, kg/kg
Sea Water (CRC Handbook)3 x 10-10mass per volume fraction, kg/L
Sea Water (Kaye & Laby)3.0 x 10-10mass per volume fraction, kg/L
Solar System (Kaye & Laby)3.7 x 10-7atom mole fraction relative to Si=1
Solar System (Ahrens)3.72 x 10-7 (5.6%)atom mole fraction relative to Si=1 (% uncertainty)
Element association of Caesium in the Mineral World
This table compares the known valid mineral species listed listed with Caesium 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 Caesium and the element listed for that row.

The second data column lists this number as a percentage of all minerals listed with Caesium.

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.
ElementValid Minerals listed with element and Caesium% of Cs mineralsRelative to % in all minerals
Oxygen29 minerals with Cs and O90.63%11.62% higher
Hydrogen17 minerals with Cs and H53.13%4.42% lower
Silicon17 minerals with Cs and Si53.13%92.99% higher
Fluorine12 minerals with Cs and F37.50%376.52% higher
Sodium9 minerals with Cs and Na28.13%51.19% higher
Potassium7 minerals with Cs and K21.88%121.66% higher
Lithium6 minerals with Cs and Li18.75%837.80% higher
Boron6 minerals with Cs and B18.75%275.72% higher
Aluminium6 minerals with Cs and Al18.75%5.77% lower
Calcium6 minerals with Cs and Ca18.75%24.71% lower
Iron5 minerals with Cs and Fe15.63%30.07% lower
Beryllium5 minerals with Cs and Be15.63%623.61% higher
Sulfur3 minerals with Cs and S9.38%57.43% lower
Titanium3 minerals with Cs and Ti9.38%32.91% higher
Copper3 minerals with Cs and Cu9.38%30.72% lower
Arsenic3 minerals with Cs and As9.38%27.82% lower
Lead3 minerals with Cs and Pb9.38%13.04% lower
Magnesium2 minerals with Cs and Mg6.25%52.98% lower
Vanadium2 minerals with Cs and V6.25%29.82% higher
Zirconium2 minerals with Cs and Zr6.25%158.77% higher
Niobium2 minerals with Cs and Nb6.25%102.46% higher
Antimony2 minerals with Cs and Sb6.25%9.15% higher
Tantalum2 minerals with Cs and Ta6.25%450.35% higher
Phosphorus1 mineral with Cs and P3.13%74.53% lower
Manganese1 mineral with Cs and Mn3.13%73.20% lower
Rubidium1 mineral with Cs and Rb3.13%4,784.38% higher
Chlorine1 mineral with Cs and Cl3.13%57.43% lower
Cerium1 mineral with Cs and Ce3.13%1.23% higher
Neodymium1 mineral with Cs and Nd3.13%268.63% higher
Tungsten1 mineral with Cs and W3.13%242.76% higher
Mercury1 mineral with Cs and Hg3.13%74.44% higher
Uranium1 mineral with Cs and U3.13%39.70% lower
Periodic Table
1H 2He
3Li 4Be 5B 6C 7N 8O 9F 10Ne
11Na 12Mg 13Al 14Si 15P 16S 17Cl 18Ar
19K 20Ca 21Sc 22Ti 23V 24Cr 25Mn 26Fe 27Co 28Ni 29Cu 30Zn 31Ga 32Ge 33As 34Se 35Br 36Kr
37Rb 38Sr 39Y 40Zr 41Nb 42Mo 43Tc 44Ru 45Rh 46Pd 47Ag 48Cd 49In 50Sn 51Sb 52Te 53I 54Xe
55Cs 56Ba 57La 72Hf 73Ta 74W 75Re 76Os 77Ir 78Pt 79Au 80Hg 81Tl 82Pb 83Bi 84Po 85At 86Rn
87Fr 88Ra 89Ac 104Rd 105Db 106Sg 107Bh 108Hs 109Mt 110Ds 111Rg 112Cn 113Nh 114Fl 115Mc 116Lv 117Ts 118Og
 
58Ce 59Pr 60Nd 61Pm 62Sm 63Eu 64Gd 65Tb 66Dy 67Ho 68Er 69Tm 70Yb 71Lu
90Th 91Pa 92U 93Np 94Pu 95Am 96Cm 97Bk 98Cf 99Es 100Fm 101Md 102No 103Lr
Default Categories CPK Electronegativity Atomic Radius Lowest Oxidation Highest Oxidation Crustal Abundance Goldschmidt Mineral Species Minerals with Cs Relative Frequency
Xenon << Caesium >> Barium


Most widespread minerals containing Caesium
This list of minerals containing Caesium 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 Caesium mineral species. It is more useful when comparing rare species rather than common species.
NameFormulaCrystal SystemMindat Localities
Pollucite(Cs,Na)2(Al2Si4O12) · 2H2OIsometric183
Galkhaite(Hg5Cu)CsAs4S12Isometric20
Pezzottaite-(Cs)Cs(Be2Li)Al2(Si6O18)Trigonal12
LondoniteCsBe4Al4(B11Be)O28Isometric10
NanpingiteCsAl2(AlSi3O10)(OH,F)2Monoclinic10
SokolovaiteCsLi2Al(Si4O10)F2Monoclinic7
Ramanite-(Cs)Cs[B5O6(OH)4] · 2H2OMonoclinic3
Cesplumtantite(Cs,Na)2(Pb,Sb3+)3Ta8O24Tetragonal2
Margaritasite(Cs,K,H3O)2(UO2)2(VO4)2 · H2OMonoclinic2
Kupletskite-(Cs)Cs2NaMn2+7Ti2[Si4O12]2O2(OH)4FTriclinic2
Photos
01680340017271926014987.jpg
Pollucite

La Speranza, San Piero in Campo, Campo nell'Elba, Livorno Province, Tuscany, Italy
06589680017865233458693.jpg
Galkhaite, etc.

Getchell Mine, Adam Peak, Potosi Mining District, Osgood Mountains, Humboldt County, Nevada, USA
07878110017272061549799.jpg
Pezzottaite-(Cs)

Sakavalana mine, Ambatovita, Mandrosonoro, Ambatofinandrahana District, Amoron'i Mania, Madagascar
02716140017864945631499.jpg
Londonite, etc.

Antsongombato gem mine, Antsentsindrano, Anosiarivo Manapa, Betafo District, Vakinankaratra, Madagascar
09999430017362077386511.jpg
Pollucite

La Speranza, San Piero in Campo, Campo nell'Elba, Livorno Province, Tuscany, Italy
06004020017797194007998.jpg
Galkhaite, etc.

Getchell Mine, Adam Peak, Potosi Mining District, Osgood Mountains, Humboldt County, Nevada, USA
01129120017866427652564.jpg
Pezzottaite-(Cs)

Sakavalana mine, Ambatovita, Mandrosonoro, Ambatofinandrahana District, Amoron'i Mania, Madagascar
07028370017362077392490.jpg
Londonite, etc.

Antsongombato gem mine, Antsentsindrano, Anosiarivo Manapa, Betafo District, Vakinankaratra, Madagascar
01680340017271926014987.jpg
Pollucite

La Speranza, San Piero in Campo, Campo nell'Elba, Livorno Province, Tuscany, Italy
06589680017865233458693.jpg
Galkhaite, etc.

Getchell Mine, Adam Peak, Potosi Mining District, Osgood Mountains, Humboldt County, Nevada, USA
07878110017272061549799.jpg
Pezzottaite-(Cs)

Sakavalana mine, Ambatovita, Mandrosonoro, Ambatofinandrahana District, Amoron'i Mania, Madagascar
08872880017271928732258.jpg
Londonite, etc.

Antsongombato gem mine, Antsentsindrano, Anosiarivo Manapa, Betafo District, Vakinankaratra, Madagascar

Localities with greatest number of different Caesium mineral species
1Dara-i-Pioz Massif, Districts of Republican Subordination, Tajikistan13 Cs minerals
2Manjaka (Sahananana), Sahatany Valley, Ibity, Antsirabe II District, Vakinankaratra, Madagascar3 Cs minerals
3Tetezantsio pegmatites, Tetezantsio-Andoabatokely Pegmatite Field, Andrembesoa, Betafo District, Vakinankaratra, Madagascar3 Cs minerals
4Stargazer Claim, O'Grady Batholith, O'Grady Lake area, Northwest Territories, Canada3 Cs minerals
5Angel Mine, Río de Los Sauces District, Calamuchita Department, Córdoba Province, Argentina3 Cs minerals
6Pakeagama Lake pegmatite, PAK Lithium Project, Pakeagama Lake Area, Kenora District, Ontario, Canada2 Cs minerals
Type V pegmatites, Giraúl pegmatite field, Moçâmedes, Namibe Province, Angola2 Cs minerals
8Pegmatite No. 31, Nanping pegmatite field, Yanping District, Nanping, Fujian, China2 Cs minerals
 
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