Frequently Asked Questions
about Cesium and

Q1. What is the purpose of the newsgroup alt.cesium?

A1. This newsgroup emerged somewhere around 1992 (the origins are a bit murky) and was intended expressly for the discussion, praise, veneration, and adoration, the posting of songs, poetry, stories, and parables of and about that most sublime of elements, the almighty Cesium. Due to persistent hijack attempts, crossposting is aggressively discouraged; persistent miscreants are netnapped and treated to the traditional Cesium Enema. As with most newsgroups, its glory days lie fossilized in the distant past, buried by layer upon layer of subsequent technology.

Q2. What is Cesium?

A2. Cesium (or Caesium) is the most sublime and electropositive of all true elements. It was discovered spectroscopically, in mineral water from Durkheim Germany by Robert Bunsen (of burner fame) and Gustaff Kirchhoff in 1860. The basis of the discovery was two, beautiful sky-blue lines from which it takes its name (Latin, caesius, sky-blue). Atomic number 55, Cesium is the heaviest of the natural alkali metals. Physically, it is a soft metal or light liquid, pale gold in color when pure, silvery-white otherwise. It melts at 28.4 C, just below body heat, and boils at 669.3 C. It has a specific gravity of 1.873, and an atomic weight of 132.9045. Actual pictures

Cesium occurs naturally in the minerals lepidolite and pollucite, the latter a hydrated aluminum cesium silicate. The richest known deposit occurs at Bernic Lake Manitoba where pollucite deposits averaging over 20% Cesium are estimated to exceed 300,000 metric tons. (Bernic Lake is also the site of the annual Cesium festival on February 24 where tons of Cesium are burned in the snow, and other Cesium madness prevails.) Cesium can be isolated by electrolysis of the fused cyanide, by vacuum distillation upon reduction of the chloride by calcium or sodium metal, and by other methods. High purity cesium salts are available for about $100/pound. According to the CRC 1987-88 handbook of Chemistry and Physics, the metal costs approximately $25/gram; however some devotees have reported costs as low as $3/gm for technical grade (99%) metal.

Cesium is an alkali metal, in the same group as lithium, sodium, potassium, and rubidium, and is similarly reactive, but to a much higher degree due to its extreme electropositivity. It reacts explosively with water, and with ice down to -116 C. In air, it catches fire spontaneously and burns with a brilliant sky-blue flame. (To the uninitiated, the flame appears purplish rather than blue; however, after sufficient meditation, study of the holy writs, and blissful hours spent in reverence before Cesium burning in her naked glory, the true blue nature of her flame is revealed.) Its hydroxide is the most powerful aqueous base known, and will eat through glass, flesh, bone, and numerous other substances. Its spectrum contains the two signature blue lines mentioned above, at 455.528 and 459.317 nm, and a number of others in the red, yellow and green. There are also two powerful lines in the near infrared at 852.113 and 894.347 nm. The existence of these lines has resulted in the experimental use of Cesium in IR decoy flares used in aerial combat.

Natural Cesium consists of a single stable isotope, Cs 133. 30 other radioactive isotopes are known, filling the range from Cs 114 to Cs 145, with half lives ranging from .57s (Cs 114), through 3x10^6y (Cs 135). Cesium 137 (half-life 30.17y) is an important fission product, and one of the most biologically hazardous components of radioactive waste and nuclear fallout. Cesium 137 is also important as a source of high-energy X-rays in radiotherapy. The 660 KeV X-rays are actually emitted by a two step process, where Cesium 137 decays by beta emission to metastable Ba137, which then emits the X-ray. A few years back, an ampule of Cs 137 from a discarded radiotherapy device was recovered from a garbage dump in Goiana Brazil by local residents. Entranced by the blue-glowing contents, they painted it on their bodies as decoration. Several deaths reportedly occurred.

In addition to being a pyrotechnic IR emitter and radiotherapy agent, Cesium is used as a getter in vacuum systems due to its high affinity for oxygen. Because of the low electron potential, Cesium and certain of its compounds (e.g. heptacesium oxide, Cs7O) have found use in photoelectric devices. It has also been used experimentally in ion propulsion systems for spacecraft, again because of its low ionization potential. Probably the best-known use is in Cesium beam atomic clocks, which are among the most accurate time measuring devices in existence. They utilize a 9193 MHz hyperfine transition in the Cs 133 atom as the the fundamental oscillator. The best of these clocks have long-term stabilities of a few parts in 10^14, or about one second in a million years. Cesium has traditionally been a strong competitor in the International Chillout (IC) competition, though lately it has been embarassed by rubidium. Cesium chloride has recently been promoted on the web as a general therapy for cancer though this use is not currently endorsed by the mainstream medical community. The greatest use of Cesium tonnage-wise is in the annual Cesium orgies sponsored by AMSWWBUW.

Q3. What about Fr***ium?

A3. We do not mention the name in alt.cesium, that false element being an upstart and pretender, vile, depraved, unnatural, and having no staying power. The longest lived isotope, Fr233 has a half life of only 22 minutes. Try to base a global time standard on that!!!

Q4. What is AMSWWBUW?

A4. AMSWWBUW stands for the Association of Mad Scientists Who Want to Blow Up the World. It is a highly secretive organization. Its activities involve large numbers of monkeys and vast quantities of Cesium. Given the indisputable fact that all persons in direct contact with the organization have mysteriously vanished from the net, the fewer questions asked, the better. Most of our information about this shadowy group derives from one Brendan Dunn, who was instrumental in the formation of alt.cesium. He, alas, is among the vanished.

Q5. Are there any songs about Cesium?

A5. Many. See ftp/pub/u/nelson/cesium_songs_col at for an ftp archive. See also Songs of Cesium.

Q6. Where can I get some Cesium?

A6. You probably can't, unless you are a "bona fide institution". If you are, any number of chemical suppliers will happily sell you as much as you can afford. For example, ICN (biologicals) lists 99.9% pure Cesium metal at $161.10 per gram. A bit steep even as Cesium goes (if you're willing to buy in bulk, you ought to be able to get it for closer to $25 or even $3 a gram). They'll also sell you ultra pure (99.999%) Cesium Chloride for $371.95/kg. Call 1-800-334-6999 toll free they say.
If you have money to burn, you might check out This outfit supplies element collectors with samples of the different elements, and they have a surprisingly large number available.

Q7. Can I eat Cesium?

A7. Yes

Q8. What will happen if I do?

A8. Read the section on the reactions of Cesium with water, and of Cesium Hydroxide with biological materials. You should also know that Cesium has been shown to have pronounced physiological action in experiments with animals, when administered in large quantities. Hyperirritability, including marked spasms has been shown to follow the administration of Cesium in amounts equal to the potassium content of the diet. Total replacement of dietary potassium with cesium in rats caused death in 10-17 days. Could explain the AMSWWBUW mystery, though no reference seem to exist for monkeys.

Q9. Are there any jokes about Cesium?

A9. There is exactly one joke about Cesium. It goes like this. So these two Cesium atoms are walking down the street. Says the first Cesium atom, "oh my god! I think I'm missing an electron". Says the second, "are you sure?" Says the first, "I'm positive". HAHAHAHAHAHA :]

Q10. Are there any neat Cesium compounds?

A10. Lots. Many of them explode with the slightest provocation or when thrown into water. For example.

Cesium Chloroxenate
Formula: CsClO3Xe
MW: 347.66
Toxicity: Unknown
Properties: Explodes
Uses: Chemical curiosity, possible rodenticide
Comments: One of the few known compounds involving a noble gas, a halogen, and an alaklai metal. Explodes if you look at it cross-eyed.

Cesium Tetraperchloratoiodate
Formula: CsI(ClO4)4
MW: 657.62
Properties: Explodes under laser irradiation (and anything else)
Uses: Curiosity, revenge against people with laser pointers.
Comments: Illustrates the +3 oxidation state of iodine, stabilized by the size of the perchlorate ion. A related compound, Iodine(III) perchlorate I(ClO4)3 also explodes under laser irradiation.

Cesium Azide
Formula: CsN3
Molecular Weight: 174.93
Melting point: 310 (Yes you can melt it)
Boiling point: Decomposes with evolution of nitrogen
Solubility in cold water 224 gm/100cc
Description: Colorless needles; Deliquesces.
Properties: Poisonous to rats. LD50 about 30 mg/kg.
Decomposes on heating, eventually producing metallic cesium and nitrogen. More stable than sodium and potassium azide.
Uses: The thermal decomposition of the azide is employed as a method of producing extremely pure, oxygen-free cesium.

Heptacesium oxide
Formula: Cs7O.
Molecular weight: 946.3
Melting point: 4.3 C (decomposes)
Description: Consists of Bronze, hexagonal crystals.
Prperties: Analysis shows presence of Cs11O3 subgroup, hence formula should be written [Cs11O3]Cs10. Decomposes violently in water to hydroxide, On slow heating to Cs3O and cesium-rich liquid.
Uses: Photocathodes, Image converters, Rat poison
Comments: One of a series of suboxides of Cesium. Produced by slow cooling of appropriate stochiometric mixture of metallic Cesium and Oxygen. Possible due to extreme solubility of oxygen in liquid cesium.

Cesium ozonate (Cesium trioxide)
Formula: CsO3.
Molecular Weight: 180.9
Description: Unstable, bright red compound.
Properties: Strong oxidizer. Decomposes with release of Oxygen. Reacts vigorously with water. Highest known oxide of Cesium, at the opposite end of the spectrum from Cs7O. Prepared by reacting Cesium or its lower oxides with ozone.
Uses: Curiosity, Exploding red ink.

Etc. etc. etc.

Q11. What are some popular Cesium products?


Q12. What should I do if I meet Cesium in dark alley?

A12. Run!!!!!!!!!

Links to other pages concerning Cesium

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