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People think of uranium as the main naturally occurring radioactive element, and as the element largely responsible for the internal heat of the earth. But thorium is just as common if not more so. Thorium also has a number of fairly common application which mean that, unlike uranium, you can actually buy some fairly easily, though not in pure form. One application not pictured below is thoriated tungsten welding rods, which contain about 2% thorium and are therefore slightly radioactive.
There was even research conducted into making nuclear power plants that ran on thorium rather than uranium fuel, though it didn't work out in the end. Reader Karen Pease kindly provided the following information about this application:"People think of uranium as the main naturally occurring radioactive element, and as the element largely responsible for the internal heat of the earth. But thorium is just as common if not more so. There was even research conducted into making nuclear power plants that ran on thorium rather than uranium fuel, though it didn't work out in the end."
There's a lot of research into thorium breeder reactors going on right now. Thorium-232 will absorb slow neutrons to produce uranium-233, which has somewhat similar properties to uranium-235 (used in conventional pressurized water reactors). India is especially pushing this technology, since they have 4 times as much thorium as uranium in reserves. Their first thorium research reactor went critical in 1996. Worldwide, a number of designs are in development. You're probably thinking of the US attempt in the Shippingport Atomic Power Station from 1977 to 1982 - it was actually a success (there was 1.3% more fissile material when they removed the rods than when they inserted them, after it generated 2.5 billion watts of power), but the reactor wasn't designed to be mass produced, and there was no follow through.
Thorium breeders have interesting potential not only to provide another fuel source many times more abundant than U-235 (which comprises only 0.7% of raw uranium), but also because of anti-proliferation qualities. Anti-proliferation thorium breeders use uranium enriched to about 20% (i.e., not enough to use in a uranium bomb) mixed in with a majority of thorium. Since the uranium is a relatively small percentage, the plutonium bred from the U-238 isn't as much of a proliferation risk as in a normal reactor, and the U-233 never becomes concentrated enough to pose a risk. Thorium reactors also don't produce much waste.
My favorite reactor design is still the Russian BREST reactor. It's a lead/bismuth cooled plutonium breeder that circulates heat via natural convection (vs the normal sodium-cooled pump-fed breeders that we used to use - the concept of using molten sodium filled with short-lived radioisotopes in a giant *concrete* building which contains highly radioactive fuel rods just sounds a bit nutty to me ;) And MONJU showed the risks when the sodium leaked and almost ate through the protective steel to the concrete). With BREST, you get high temperature heating (so you can directly split hydrogen from water with the heat if so desired), a nonreactive and self-containing coolant, safety even if all the coolant pumps fail, little built up pressure, and of course, you have a use for all of that U-238 and notably reduced radioactive waste. Nuclear reactor designs have really been advancing, and it's interesting to read about what's being worked on.
In case you're curious, the reason plutonium breeders need to use liquid metal coolant instead of water is because U-238 only becomes plutonium when hit with fast neutrons; the water moderator in light water reactor slows them down. Thorium reactors, on the other hand, use slow neutrons to breed U-233.
- Karen
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Lantern mantle.
Amazingly, Coleman-type camping lanterns used to contain some radioactive thorium oxide. It's an incandescent material that greatly increases the light output of the lantern when it's heated in the flame. There are non-radioactive alternatives, mainly other rare earth oxides, but they are more expensive. We know this mantle contains radioactive thorium because the donor, who works for the Environmental Health & Safety department at the University of Illinois at Urbana-Champaign, tested it with a Geiger counter.
The sound for this sample is from the Geiger counter.
I've got one mantle in a lead cup in the table, and another one in the Hot Box.
Source: Hardware Store
Contributor: Trish Craig
Acquired: 28 May, 2002
Text Updated: 12 March, 2007
Price: Donated
Size: 2"
Purity: <20%
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Scary stuff.
This is a mixture of powder and lumps of actual thorium metal. It's radioactively quite hot, and because thorium emits high energy particles, the radiation is not stopped by the miserable sixteenth inch of lead equivalent in our Hot Box display case. I made a special lockable container, called The Can to hold this and the uranyl nitrate.
On September 17, 2002 one chip from this sample was de-accessioned from the Table to be sent to David Franco in small thanks for the many elements he has contributed. I made a lead tamale to hold it in shipping:
Lord only knows what the postal authorities would think if they found this.
Click the source link for an interesting story about where this sample came from.
Source: Tryggvi Emilsson and Timothy Brumleve
Contributor: Tryggvi Emilsson and Timothy Brumleve
Acquired: 6 September, 2002
Price: Donated
Size: 1"
Purity: 99.9%
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Sample from the RGB Set.
The Red Green and Blue company in England sells a very nice element collection in several versions. Max Whitby, the director of the company, very kindly donated a complete set to the periodic table table.
To learn more about the set you can visit my page about element collecting for a general description or the company's website which includes many photographs and pricing details. I have two photographs of each sample from the set: One taken by me and one from the company. You can see photographs of all the samples displayed in a periodic table format: my pictures or their pictures. Or you can see both side-by-side with bigger pictures in numerical order.
The picture on the left was taken by me. Here is the company's version (there is some variation between sets, so the pictures sometimes show different variations of the samples):
Source: Max Whitby of RGB
Contributor: Max Whitby of RGB
Acquired: 25 January, 2003
Text Updated: 11 August, 2007
Price: Donated
Size: 0.2"
Purity: 99.5%
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Sample from the Everest Set.
Up until the early 1990's a company in Russia sold a periodic table collection with element samples. At some point their American distributor sold off the remaining stock to a man who is now selling them on eBay. The samples (except gases) weigh about 0.25 grams each, and the whole set comes in a very nice wooden box with a printed periodic table in the lid.
Radioactive elements like this one are represented in this particular set by a non-radioactive dummy powder, which doesn't look anything like the real element.
To learn more about the set you can visit my page about element collecting for a general description and information about how to buy one, or you can see photographs of all the samples from the set displayed on my website in a periodic table layout or with bigger pictures in numerical order.
Source: Rob Accurso
Contributor: Rob Accurso
Acquired: 7 February, 2003
Text Updated: 29 January, 2009
Price: Donated
Size: 0.2"
Purity: 0%
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Radioactive lens.
For a while thorium was added to lens glass to increase its index of refraction (which allows the lens to be thinner and lighter). It also increases its level of radioactivity, from zero to quite a bit: This rather small lens registers about 4000 counts per minute on my Geiger counter. A large compound camera lens could be quite radioactive, which is one reason they stopped using thorium this way.
Another reason is that over a period of time, the glass turns yellow. Interestingly, this is not due to any sort of chemical reaction, it's caused by the radioactivity itself. Charged particles shot out when the thorium decays knock electrons out of place in the glass. Because glass is an insulator other electrons can't easily move in to fill the hole, and a so-called color center is formed, in which the missing electron allows light to be absorbed in a previously transparent substance. Heating the glass can allow enough electron mobility to wipe out the color, or so I read.
Source: eBay seller heruur
Contributor: Theodore Gray
Acquired: 3 June, 2003
Price: $25
Size: 0.5"
Purity: 1%
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Cutout sheets, 20g.
These foils (some thin, some thickish) are pure thorium metal. They were part of a larger batch purchased by Max Whitby for his commercial element collections: This bunch is the element tax I impose on any samples that pass through my hands.
It's very odd, to me at least, to think of elements like thorium and uranium as metals, but they really are ordinary metals that you can bend, roll, fabricate, etc. Of course, you wouldn't want to do any of those things without a high level of care to be sure you never came in contact with dust from the operations, as thorium dust is extremely dangerous, as is uranium dust.
These clippings are kept in The Can along with my other potentially dangerous radioactives. The Can, in turn, is now kept in The Safe, because after the acquisition of this sample I decided there was enough material in my hands that if it were ever stolen, I would be in trouble. The thief would face minimal danger unless they really completely ignored the prominent radioactive labels, but I would face a lot of questions about how I had been storing the samples and whether I had provided a proper level of security for them. I don't think anyone could argue that the current arrangement is not prudent.
The purity of this sample is listed as 99% because that's what it was labeled as, but I suspect the purity is actually significantly higher, because the company it comes from generally works only with 99.99% thorium metal. They are probably just being conservative in rating this material since they know we don't require higher purity. The source is listed as anonymous not because it's shady: This material was actually purchased in an entirely above-board and legal way from a company that supplies thorium and other chemicals to industry. They just don't want to get a lot of calls from element collectors who want to buy thorium, because they do not sell thorium to the public (way, way too much hassle and potential liability).
Interestingly, they sent this material to me packaged in a sturdy box with a hazardous-materials can inside, and inside that a lead tamale very similar to the one I made for sending a few chips of thorium to David Franco earlier:
It seems I guessed right about the correct method for shipping thorium, because these people certainly know what they are doing.
I chose this sample to represent its element in my Photographic Periodic Table Poster. The sample photograph includes text exactly as it appears in the poster, which you are encouraged to buy a copy of.
Source: Anonymous
Contributor: Max Whitby of RGB
Acquired: 25 July, 2003
Text Updated: 11 August, 2007
Price: Donated
Size: 1"
Purity: 99%
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Vacuum tube.
This is an Eimac 4-65A/8165 radio tube that contains a thoriated tungsten (i.e. radioactive) electrode. They are quite common actually, or at least used to be when vacuum tubes in general were common.
Source: MDB Ventures
Contributor: Theodore Gray
Acquired: 7 August, 2004
Price: $30
Size: 3"
Purity: 2%
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Bottle of Radithor.
Ah, now this is some real history. I wrote an article a few years ago about the radioactive health craze of the 1920's and 30's, when people felt that radiation was good for you and the government shut down as fraudulent anyone advertising radioactive health products that didn't actually contain enough radioactive material to match the claims of their ads.
This is one product they did not, at first, have any problem with. Radithor was the premier brand of radioactive water, containing significant amounts of radium and thorium. How much? Consider for a moment that this bottle has been empty probably for decades, but the cork is still strongly radioactive from whatever residue may have soaked into it before someone drank the contents.
It all came to an end in 1932 when the government reversed course and decided that radiation is actually bad for you. The FDA was created in part to regulate (i.e. ban) these radioactive quack medical cures.
And Radithor had a lot to do with that. It was so potent that people started seriously dying from it, including the well-publicized case of Eben Byers, a millionaire who could afford to drink three bottle a day, until, as the New York Times reported at the time "his jaw came off".
I am thrilled to have an actual Radithor bottle, in my opinion the premier historical radioactive quack medical collectible. Now, if only I could get a full one.
Source: dealer248
Contributor: Theodore Gray
Acquired: 20 August, 2006
Text Updated: 12 March, 2007
Price: $81
Size: 2.5"
Purity: <1%
Sample Group: Medical
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Antique lantern mantle.
Lantern mantles, which glow very brightly when heated by an oil flame in a camping lantern, used to be made with thorium oxide as the primary incandescent material. Thorium was used right up the 1990's, but has now be replaced with various other rare earth oxides.
These were claimed by the seller to date from the early 1900's, and considering how fragile they are, I can believe it. Two of the three I bought were basically smashed to crumbs (radioactive crumbs) on arrival, the third was in perfect condition for photography, but sadly lost a chuck due to an accidental tap on being replaced in its container. Sad, but it would almost certainly have crumbled on its own soon anyway, the material is basically turning to dust.
This is a picture of the nice cardboard can it came in:
Source: eBay seller boco007
Contributor: Theodore Gray
Acquired: 11 March, 2007
Text Updated: 12 March, 2007
Price: $10
Size: 2"
Purity: <20%
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Cutout sheets, 20g.
This was part of a larger batch purchased by Max Whitby for his commercial element collections: I piggybacked the purchase of this material from the same source, for a sum that must remain confidential per our agreement with the source, who also wishes to remain anonymous. (Nothing illegal mind you, ownership and sales of thorium metal in small quantities is perfectly legal, they just don't want anyone hassling them to sell more of it.)
This sheet is about 1/16" thick, not just a foil, a real plate, heavy due to the high density. The photograph shows it as it originally came to me, it is now 3/4" shorter because I cut off a 15 gram (out of a total of 50 grams originally) rectangle of it to trade for a depleted uranium projectile. Please note that if you're looking for a serious chuck of thorium metal (a) good luck and (b) don't bother asking me, I am not prepared to trade any of this material for blood or money. The only thing I might trade it for is a seriously unusual sample of something I don't have anything like: A significant historical object, genuine DU tank penetrator, that kind of thing.
The date listed is the date I officially added this to the collection, I actually acquired it several years earlier. And in late 2007, preceding paragraph notwithstanding, I traded this sample for the next one listed under thorium, a square rod in a glass ampule. OK, not just for the rod, I got something else that must remain confidential for the time being, but will show up here eventually.
Source: Anonymous
Contributor: Max Whitby of RGB
Acquired: 16 March, 2007
Text Updated: 14 June, 2008
Price: Confidential
Size: 2.3"
Purity: 99%
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Square rod.
This glass-ampuled square rod of thorium was received in trade for the cut sheet listed in the previous sample description under thorium. It's permanently sealed in a glass ampule to prevent oxidation and to eliminate the possibility of radioactive contamination.
Source: Anonymous
Contributor: Anonymous
Acquired: 14 June, 2008
Text Updated: 14 June, 2008
Price: Confidential
Size: 2"
Purity: 99%
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Thorite.
This is a very rare thorium mineral. Not much to look at, but it has a well-defined crystal structure and it's hot enough that when it fell under a bunch of stuff, I had no trouble locating it with a Geiger counter. (This is one of the great advantages of radioactive things: You can never really loose them. Not so the osmium pellet I'm probably never going to find.)
The price reflects the rarity of this species.
Source: eBay seller mineralman999
Contributor: Theodore Gray
Acquired: 3 June, 2005
Price: $90
Size: 0.5"
Composition: (Th,U)SiO
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Monazite Sand.
Monazite is a thorium-bearing mineral that occurs in sand deposits in a number of places around the world. Only a small proportion of the sand in this sample is actually monazite: It is probably somewhat selected compared to normally occurring sand deposits, but not much. It's kind of remarkable, really, that you can collect thorium just by scooping it up with a shovel.
Source: Max Whitby of RGB
Contributor: Max Whitby of RGB
Acquired: 20 September, 2005
Price: Donated
Size: 1.5"
Composition: (Ce,La,Nd,Th)PO4
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Aeschynite.
The card that came with this shale-like blackish mineral says the following about the name: "From Gk. aeschyne, shame, alluding to the inability of chemists at the time of its discovery to separate some of its constituents". Hm, I wonder if it was the chemists who came up with this name, or the geologists who gave it to them to analyze.
This specimen is from Molland in Iveland, Norway. I bought it for its thorium content: Not that many minerals contain thorium and I'm trying to collect them all.
Reader Magnus Alvestad sent this interesting information about Iveland:Hi. I noticed that your Aeschynite sample is from Iveland in Norway. The small community of Iveland is actually famous for their mines and minerals. Here's a folder with some information about a local exhibition. They also have at least 5 mines that are open to the public for a small price, where you can dig for minerals yourself.
Source: SoCal (Nevada), Inc
Contributor: Theodore Gray
Acquired: 20 September, 2005
Text Updated: 1 December, 2008
Price: $29
Size: 1.5"
Composition: (Y, Ca, Fe, Th)(Ti, Nb)2(O, OH)6
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Thorite.
This is a lovely shiny crystal of thorite, a rare radioactive mineral, from Mt. Zagi, Pakistan. The price reflects the rarity of this species more so than its beauty, though this one is really quite attractive.
Source: eBay seller 4jdk
Contributor: Theodore Gray
Acquired: 25 September, 2005
Price: $76
Size: 0.5"
Composition: (Th,U)SiO
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Zirconolite.
Description from the source:
Zirconolite var. Polymignite ((Ca Fe Y Th) (Nb Ti Ta Zr) O4 orth.), Stavern (Fredriksva"rn), Larvik, Vestfold, Norway. Black, fractured on matrix. 2,5x1,4x1,2 cm; 3 g.
Source: Simone Citon
Contributor: John Gray
Acquired: 30 September, 2008
Text Updated: 1 October, 2008
Price: Trade
Size: 1"
Composition: (CaFeYTh)(NbTiTaZr)O4
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Euxenite.
Description from the source:
Euxenite ( (Y Ca Ce U Th) (Nb Ta Ti)2 O6 orth.), Trout Creek Pass, Chafee Co. Colorado, USA. Crystal cluster, nice and rare example. 2x1,5x1 cm; 14 g with box.
Source: Simone Citon
Contributor: John Gray
Acquired: 30 September, 2008
Text Updated: 1 October, 2008
Price: Trade
Size: 0.75"
Composition: (YCaCeUTh)(NbTaTi)2O6
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Euxenite from Jensan Set.
This sample represents lutetium in the "The Grand Tour of the Periodic Table" mineral collection from Jensan Scientifics. Visit my page about element collecting for a general description, or see photographs of all the samples from the set in a periodic table layout or with bigger pictures in numerical order.
Source: Jensan Scientifics
Contributor: Theodore Gray
Acquired: 10 January, 2009
Text Updated: 10 January, 2009
Price: Anonymous
Size: 0.6"
Composition: (Y,Ca,Ce,Lu,U,Th)(Nb,Ta,Ti)2O6
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Monazite.
Description from the source:
Monazite ( (Ce La Nd Th) P O4 mon.), Steli near Tveit, Iveland, Nordge. Extremely well crystallized example. 0,8x0,4x0,4 cm; 5 g with box.
Source: Simone Citon
Contributor: John Gray
Acquired: 28 January, 2009
Text Updated: 29 January, 2009
Price: Trade
Size: 0.3"
Composition: (CeLaNdTh)PO4
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Insane mineral capsules.
These minerals capsules are called "Immune Boost 77", from Morningstar Minerals. They are either being incredibly honest, or they really don't understand what they're saying when they list what amounts to nearly the entire periodic table on the label, as the "trace minerals" they contain.
Here is the list in all its glory, typed in by my daughter in exchange for my paying for a membership in the Miley Cyrus fan club: Antimony, Barium, Beryllium, Bismuth, Boron, Bromine, Calcium, Carbon, Cerium, Cesium, Chloride, Chromium, Cobalt, Copper, Dysprosium, Erbium, Europium, Florine, Gadolinium, Gallium, Germanium, Gold, Hafnium, Holmium, Indium, Iodine, Iridium, Iron, Lanthanum, Lithium, Lutetium, Magnesium, Manganese, Molybdenum, Neodymium, Niacin, Nickel, Niobium, Osmium, Palladium, Phosphorus, Platinum, Potassium, Praseodymium, Rhenium, Rhodium, Rubidium, Ruthenium, Samarium, Scandium, Selenium, Silicon, Silver, Sodium, Strontium, Sulfur, Tantalum, Thallium, Thorium, Tellurium, Terbium, Thulium, Tin, Titanium, Tungsten, Vanadium, Ytterbium, Yttrium, Zinc, Zirconium.
Some of them are just silly, like thulium, which has absolutely no biological function. Others are a bit scarier, like thallium and thorium that are deadly poisons, and tellurium, which makes you smell of rotten onions for weeks.
Basically what they've done is list everything that occurs in even trace amounts in mixed monazite sand, which is kind of what the stuff inside looks like. The only reason they aren't seriously harmful (I assume) is that most of these are not actually present in any meaningful quantity.
My attention is drawn to these and other similar mineral supplements every time I decide to see if anything interesting has popped up on eBay for one or another of the obscure rare earths. Generally speaking if you search eBay for those guys you get very little of interest unless you turn on the option to search the text of the item description as well as the titles. Then you get lots of trace mineral supplements that one can only hope don't actually contain them.
Source: eBay seller grandma-adams
Contributor: Theodore Gray
Acquired: 24 March, 2009
Text Updated: 29 March, 2009
Price: $15
Size: 0.75"
Composition: SbCsDyErEuGdHfHoInLaLuNdPrSmScThTlTeTbTmYbY
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Himalayan sea salt.
There is a list of 84 elements that seems to pop up repeatedly in the ingredient lists of "natural" mineral products, supplements, pills, and the like. Even, it turns out, in salt. Here then is the list of minerals claimed to be found in all-natural organic Himalayan sea salt:hydrogen, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluoride, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chloride, calcium, scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, arsenic, selenium, bromine, rubidium, strontium, yttrium, zirconium, niobium, molybdenum, ruthenium, rhodium palladium, silver, cadmium, indium, tin, antimony, tellurium, iodine, cesium, barium, lanthanum, cerium, praseodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, thallium, lead, bismuth, polonium, astatine, francium, radium, actinium, thorium, protactinium, uranium, neptunium and plutonium. I wish someone would tell these people that, for example, neptunium and plutonium do not occur in nature at all, let alone in salt. Unless, I suppose, if you count nuclear fallout as a "natural" source of ingredients.
What bothers me most is what this says about the level of scientific literacy, both of the people selling the stuff, and the people buying it. Does no one actually read the list? Or do they read it an not realize how preposterous it is? It's enough to make you despair for the future of mankind.
Pretty salt, though.
Source: eBay seller saltwonders
Contributor: Theodore Gray
Acquired: 28 March, 2009
Text Updated: 4 April, 2009
Price: $15
Size: 0.25"
Composition: NaClSbCsDyErEuGdHfHoInLaLuNdPrSmScThTlTeTbTmYbY
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Thorium shavings. (External Sample)
This is a sample of thorium metal I had in hand briefly: It consists of nice little shavings of thorium metal ampuled in glass under argon to prevent oxidation.
Location: Anonymous
Photographed: 26 September, 2008
Text Updated: 27 September, 2008
Size: 3"
Purity: 99%
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