My periodic table poster is now available! For years growing up I thought cobalt was radioactive. This probably had something to do with the Planet of the Apes movies, and the fact that a radioactive isotope, cobalt-60, is widely used in medicine. Of course nothing of the sort is true: Cobalt is perfectly stable, and not even particularly toxic. It's commonly used as an alloying element with iron (cobalt steel tool bits, etc). It's also a component of special alloys used for artificial body parts, but is rarely used in pure form. Compare at other websites: periodictable.com Wikipedia WebElements Museum Display Minerals Translations and Etymology Science Fiction (Main Site) Comics Collections: Elements in the Human Body Minerals, Alloys, and Compounds Elements Popular in Collections Poster Samples Samples with Rotatable Images Samples with Sounds Samples with High Resolution Spin Movies Anode button. Purchased from Neil Lipson (Lipson@postoffice.att.net) after contact through eBay. I'm very unclear on what process this odd item was a result of, but clearly electro-accumulation is a reasonable claim. It's quite peculiar. I have a pound of very similar buttons made of nickel instead. Source: Neil Lipson Contributor: Theodore Gray Acquired: 29 May, 2002 Price: $5 Size: 1.25" Purity: >99% Another anode button. This one was donated by David Franco in exchange for Mathematica T-shirts. It's similarly peculiar. Source: David Franco Contributor: David Franco Acquired: 11 June, 2002 Price: Donated Size: 1.25" Purity: >99% Top of knee joint. This is the top of an artificial knee joint: I've removed the plastic block that attaches just underneath this metal part, and which mates with the double-ball of the other half, which you can see under aluminum. Unfortunately they seem to be a different brand or something because the parts don't fit each other. I originally thought these were titanium, but the source, Paul Wellin's Brother, reports as follows: "The top of knee joint and the hip joint ball attachment are probably made of a different alloy, cobalt-chrome, for increased strength and decreased flexibility as compared to titanium." I don't know whether there is more cobalt or more chromium in the alloy, so I've somewhat arbitrarily chosen to put them under cobalt. Source: Paul Wellin Contributor: Paul Wellin Acquired: 14 June, 2002 Price: Donated Size: 2.5" Purity: <60% Sample Group: Body Parts+Medical Hip joint ball attachment. This is the part of an artificial hip which is inserted into the long bone of the leg, whatever that's called. Then a ball screws onto the end of it. The middle section is coated with some kind of rough probably ceramic surface, to encourage bone to grow into and attach to it. The ball fits into a socket which you can see under titanium. Source: Paul Wellin Contributor: Paul Wellin Acquired: 14 June, 2002 Price: Donated Size: 5" Purity: <60% Sample Group: Body Parts+Medical Odd-shaped nodule. You can always count on Lipson for a strange lump of something. Heaven knows where this one is from. Source: Neil Lipson Contributor: Theodore Gray Acquired: 10 January, 2003 Price: $5.50 Size: 2" Purity: >95% 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 Price: Donated Size: 0.2" Purity: 99.5% 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 gasses) 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. 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 Price: Donated Size: 0.2" Purity: >99% Electrowinning plate. This is almost certainly a plate that came from the electrolytic extraction of cobalt from its ore, or from an electrolytic purification process. Cobalt was dissolved in a solution and electricity was used to plate it out onto an electrode. Very pretty, very heavy. Source: eBay seller akilawolf Contributor: Theodore Gray Acquired: 5 June, 2003 Price: $15.50 Size: 1.2" Purity: 99.9% Maybe a training cobalt-60 source. This item was sold as a training simulator of a technetium generator. It isn't. There is such a thing as a technetium generator, but they don't look anything like this. Instead, it's possible that it is a training simulator of a cobalt-60 gamma ray source or thermoelectric battery core. But that's just guessing: The only thing I can say for sure is that neither the core nor the shield are made of anything but ordinary steel, and they are totally non-radioactive. Any ideas, let me know. Source: eBay seller aztecjaguarwarrior Contributor: Theodore Gray Acquired: 20 August, 2003 Price: $15 Size: 3" Purity: 0% Sample Group: Medical Shiny hip joint. I'm somewhat guessing by classifying this as a cobalt-chrome alloy, but it's a reasonable guess. Definitely too heavy to be titanium, the other plausible metal. Source: eBay seller mickw16 Contributor: Theodore Gray Acquired: 20 December, 2003 Price: $60 Size: 6" Purity: <60% Sample Group: Body Parts+Medical Knee joint. I'm guessing by classifying this as a cobalt-chrome alloy, but it's a reasonable guess. I think this may be an older design, and may even be stainless steel: I need to test it. It's a very lovely piece of machinery, though you would click a bit walking with it. What's really fun is the thoughtful labeling that identifies the front. Otherwise you might end up with a knee that bends the wrong way, if your doctor got it backwards, which, I suppose, someone must have been worried about or they wouldn't have put the label on. Source: eBay seller smeezle Contributor: Theodore Gray Acquired: 20 December, 2003 Price: $15 Size: 9" Purity: <60% Sample Group: Body Parts+Medical Museum-grade sample. In early 2004 Max Whitby and I started selling individual element samples identical or similar to the samples we use in the museum displays we build. These are top-quality samples presented in attractive forms appropriate to the particular element. They are for sale from Max's website and also on eBay where you will find an ever-changing selection of samples (click the link to see the current listings). This vial of cobalt contains 50+ grams of electrolytic cobalt plate, very beautiful lustrous stuff. Source: Theodore Gray Contributor: Theodore Gray Acquired: 24 February, 2004 Price: See Listing Size: 2" Purity: >99% Sample Group: RGB Samples Another hip joint. This may or may not be cobalt-chrome alloy like my other hip joints. It's older and I don't know the history of what alloys were used for these devices, so eventually I'll need to test it. This one is nice because it came with the ball and plastic socket that is missing from my other hip joints. The plastic socket would have fit into one of the cups you can see listed under titanium. Source: eBay seller sushack Contributor: Theodore Gray Acquired: 28 April, 2004 Price: $36 Size: 7" Purity: <60% Sample Group: Body Parts+Medical Particularly beautiful plate. This is a particularly pretty bit of electrolytic plate, which I picked out for the purpose of making a high-resolution 360 rotation image (click turntable icon to see it). 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: Theodore Gray Contributor: Theodore Gray Acquired: 12 September, 2005 Price: $0.10 Size: 1" Purity: >99% Sputtering target. Another nice sputtering target from Ethan, who seems to have a lot of them. Source: Ethan Currens Contributor: Ethan Currens Acquired: 30 September, 2007 Price: Donated Size: 2.5" Purity: 99.99% Element coin. Dave Hamric sells element samples under the name Metallium. He's developed a line of coins struck out of various common and uncommon metals: They are quite lovely, and very reasonably priced, considering the difficulty of creating some of them. Here is the back side of this coin (click either picture to see it larger): Click the Sample Group link below to see many other coins made of various elements, or click the link to his website above if you want to buy one like this. Source: Dave Hamric Contributor: Theodore Gray Acquired: 24 December, 2007 Price: $24 Size: 0.75" Purity: >99% Sample Group: Coins Erythrite from Jensan Set. This sample represents cobalt 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: Jensan Scientifics Acquired: 17 March, 2003 Price: Donated Size: 1" Composition: Co3(AsO4)2.8H2O Manganese Nodule. Do you remember when manganese nodules were going to be the next great gold rush? When a great new natural resource was going to be unleashed just as soon as someone figured out how to dredge them up from the incredibly deep ocean? Did you ever wonder if there might not be some in shallower water? Well, guess what: The whole thing was a complete fabrication. The CIA wanted to recover a Soviet submarine that had gone down in very, very deep water in the Pacific, and they needed a cover story because they knew that there was no way they could build and deploy the highly specialized kind of ship required to recover something from such great depth without the Russians (who knew exactly where their submarine had gone down) figuring out that something was up. So they enlisted Howard Hughes, the richest man in the world at the time and a notable nutcase, to pretend that he thought these manganese nodules, which just happened to exist only at great depths, were the next big thing. He built a large, specialized deep sea recovery ship, the Glomar Explorer, and sent it to find, um, um, manganese nodules, that's right, we're looking for manganese nodules. They actually did find the Soviet submarine and were able to recover parts of it. Eventually people forgot about the manganese nodules. If you don't believe me, read this report on the subject: http://www.fas.org/irp/program/collect/jennifer.htm This particular nodule was recovered from 5100m of water in the central pacific by the MS Valdiva working for the Metallgesellschaft AG, Frankfurt am Main. I wonder if they thought they were going to get rich. Source: eBay seller mitryrock Contributor: Theodore Gray Acquired: 3 June, 2003 Price: $20.50 Size: 1" Composition: MnNiCuCo Arc-melted magnetic alloy. Description supplied by the source: This is another arc-melted button of a particular alloy of iron-cobalt slated to be used for magnetism research. I chose to send you this particular sample because of the beautiful surface and crystal grains visible. Source: Ethan Currens Contributor: Ethan Currens Acquired: 21 March, 2008 Price: Anonymous Size: 1.5" Composition: FeCo    My periodic table poster is now available!