HHomeBackground Color:He
LiBeCobalt Pictures PageBlack White GrayBCNOFNe
NaMgCobalt Technical DataAlSiPSClAr
KCaCobalt Isotope DataScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr
RbSrYZrNbMoTcRuRhPdAgCdInSnSbTeIXe
CsBaLaCePrNdPmSmEuGdTbDyHoErTmYbLuHfTaWReOsIrPtAuHgTlPbBiPoAtRn
FrRaAcThPaUNpPuAmCmBkCfEsFmMdNoLrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg
Cobalt     

Cobalt

Atomic Weight 58.933194
Density 8.9 g/cm3
Melting Point 1495 °C
Boiling Point 2927 °C
Full technical data

Cobalt is used in pigments, notably cobalt blue, and in high-strength, high-temperature steel alloys. High purity cobalt is obtained by electrolyzing cobalt ions out of solution, resulting in bumpy plate like this.

Scroll down to see examples of Cobalt.
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Cobalt gum

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Cobalt gum.
Not sure why anyone would name their gum after cobalt, but they did. No cobalt in it, I hope.
Source: Grocery Store
Contributor: Theodore Gray
Acquired: 16 October, 2009
Text Updated: 18 October, 2009
Price: $2
Size: 3"
Purity: 0%
Cobalt Cobalt blue paint

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Cobalt blue paint.
Cobalt blue pigmented paint.
Source: eBay seller charltonmills
Contributor: Theodore Gray
Acquired: 16 April, 2009
Text Updated: 17 April, 2009
Price: $12
Size: 1"
Purity: <30%
Cobalt Cobalt-glass head

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Cobalt-glass head.
A cobalt-blue glass head.
Source: eBay seller homedecorshops
Contributor: Theodore Gray
Acquired: 24 March, 2009
Text Updated: 24 March, 2009
Price: $25
Size: 10"
Purity: 0.005%
Cobalt Cobalt-glass insulator

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Cobalt-glass insulator.
Pretty and fairly big antique cobalt-blue glass insulator. Amazing the price things things will fetch on eBay.
Source: eBay seller gigioleen
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $77
Size: 4"
Purity: 0.005%
Cobalt Cobalt-glass insulator

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Cobalt-glass insulator.
Pretty little antique cobalt-blue glass radio strain insulator. Amazing the price things things will fetch on eBay.
Source: eBay seller radaru
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $30
Size: 2"
Purity: 0.005%
Cobalt Cobalt-glass cat thing

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Cobalt-glass cat thing.
Not sure what this thing is, but it's made of cobalt-blue glass.
Source: eBay seller alteglasslady
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $5
Size: 3"
Purity: 0.005%
Cobalt Cobalt-glass candle holder

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Cobalt-glass candle holder.
A cobalt-blue glass candle holder.
Source: eBay seller 517trinket
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $7
Size: 2.5"
Purity: 0.005%
Cobalt Cobalt-glass vase

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Cobalt-glass vase.
A cobalt-blue glass vase.
Source: eBay seller auntncb
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $10
Size: 7"
Purity: 0.005%
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Cobalt-glass bottle

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Cobalt-glass bottle.
Another pretty cobalt-blue glass bottle.
Source: Nick Mann
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: Donated
Size: 8"
Purity: 0.005%
Cobalt Cobalt-glass bottle

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Cobalt-glass bottle.
Pretty cobalt-blue glass bottle (actually made with cobalt, though very little does the job).
Source: Nick Mann
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: Donated
Size: 8"
Purity: 0.005%
Cobalt Cobalt-steel milling bit

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Cobalt-steel milling bit.
This is a lovely 1.5" diameter, 6-flute cobalt steel square end mill. It would be used in a milling machine to cut a variety of metals. I list it under cobalt even though the main ingredient is of course iron, because cobalt is the ingredient that distinguishes this alloy from other steel alloys with different properties. Cobalt steel is particularly hard, and thus suitable for cutting tools.
Source: eBay seller valpone
Contributor: Theodore Gray
Acquired: 9 February, 2009
Text Updated: 8 February, 2009
Price: $15
Size: 1.5"
Purity: <5%
Cobalt Element coin

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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
Text Updated: 24 December, 2007
Price: $24
Size: 0.75"
Purity: >99%
Sample Group: Coins
Cobalt Sputtering target

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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
Text Updated: 19 November, 2007
Price: Donated
Size: 2.5"
Purity: 99.99%
Cobalt Particularly beautiful plate

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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.
Periodic Table Poster

Source: Theodore Gray
Contributor: Theodore Gray
Acquired: 12 September, 2005
Text Updated: 4 May, 2007
Price: $0.10
Size: 1"
Purity: >99%
Cobalt Another hip joint

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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
Text Updated: 11 March, 2007
Price: $36
Size: 7"
Purity: <60%
Sample Group: Body Parts+Medical
Cobalt Museum-grade sample

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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
Text Updated: 11 August, 2007
Price: See Listing
Size: 2"
Purity: >99%
Sample Group: RGB Samples
Cobalt Knee joint

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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
Text Updated: 11 March, 2007
Price: $15
Size: 9"
Purity: <60%
Sample Group: Body Parts+Medical
Cobalt Shiny hip joint

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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
Text Updated: 11 March, 2007
Price: $60
Size: 6"
Purity: <60%
Sample Group: Body Parts+Medical
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Maybe a training cobalt-60 source

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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
Text Updated: 11 March, 2007
Price: $15
Size: 3"
Purity: 0%
Sample Group: Medical
Cobalt Electrowinning plate

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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%
Cobalt Sample from the Everest Set

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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.

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: >99%
Cobalt Sample from the RGB Set

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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%
Cobalt Odd-shaped nodule

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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%
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Hip joint ball attachment

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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
Text Updated: 11 March, 2007
Price: Donated
Size: 5"
Purity: <60%
Sample Group: Body Parts+Medical
Cobalt Top of knee joint

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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
Text Updated: 11 March, 2007
Price: Donated
Size: 2.5"
Purity: <60%
Sample Group: Body Parts+Medical
Cobalt Another anode button

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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%
Cobalt Anode button

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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%
Cobalt Hastelloy propeller

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Hastelloy propeller.
Propeller made of the nickel superalloy Hastelloy C.
Source: eBay seller indcomixing
Contributor: Theodore Gray
Acquired: 25 April, 2009
Text Updated: 30 April, 2009
Price: $150
Size: 4"
Composition: NiCrMoFeCo
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Pentlandite

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Pentlandite.
Pentlandite rich in cobalt.
Source: Jensan Scientifics
Contributor: Theodore Gray
Acquired: 25 April, 2009
Text Updated: 27 April, 2009
Price: Anonymous
Size: 0.5"
Composition: (FeNiCo)9S8
Cobalt Cobalt Chloride

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Cobalt Chloride.
Cobalt Chloride, very pure, but sadly not mine, just borrowed for photography.
Source: Anonymous
Contributor: Anonymous
Acquired: 17 April, 2009
Text Updated: 17 April, 2009
Price: None
Size: 0.25"
Composition: CoCl2
Cobalt Cobalt bromide.

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Cobalt bromide.
Cobalt bromide, very pure, but sadly not mine, just borrowed for photography.
Source: Anonymous
Contributor: Anonymous
Acquired: 17 April, 2009
Text Updated: 17 April, 2009
Price: None
Size: 0.25"
Composition: CoBr2
Cobalt Cobalt steel bit

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Cobalt steel bit.
A cobalt-steel roughing end mill. The serrated flutes remove material rapidly, but leave a rough surface.
Source: eBay seller singlepoint
Contributor: Theodore Gray
Acquired: 11 March, 2009
Text Updated: 12 March, 2009
Price: $13
Size: 4"
Composition: FeMoCo
Cobalt M42 molybdenum cobalt steel bit

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M42 molybdenum cobalt steel bit.
A typical fairly large milling machine bit called an end mill. It is made of M42 molybdenum-cobalt steel allow, often called cobalt steel because even though it has more molybdenum than cobalt in it, it is an alloy distinguished by its cobalt content being higher than that in most others steels.
Source: eBay seller aztool-jerry
Contributor: Theodore Gray
Acquired: 11 March, 2009
Text Updated: 12 March, 2009
Price: $15
Size: 4"
Composition: FeMoCo
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Compact flash card hard drive

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Compact flash card hard drive.
This is just crazy. When I first heard about these things my jaw literally dropped (not literally). They are obsolete now, having been hopelessly beaten by solid state flash memory, but in their day they were the highest capacity compact memory cards available, up to 8GB by 2008 (by which time 64GB flash memory cards were available).
And they are mechanical hard disk drives. Let me remind you of the dimensions of a compact flash card (type II): 1.4" x 1.7" x 0.2" (36.4mm x 42.8mm x 5mm). The platter in this drive is about 1" (2.5cm) in diameter. It's just crazy small. There's an electric motor spinning the platter, an electro-magnet that moves the read-write heads back and forth, the whole works, plus of course all the control and interface electronics, packing into no space.
I stand in awe of this device.
The platters are aluminum, the electronics are silicon, the wiring is copper, the magnets are neodymium iron boron, and the magnetic coating is iron and cobalt based.
Source: Electronics Store
Contributor: Theodore Gray
Acquired: 28 February, 2009
Text Updated: 1 March, 2009
Price: $100
Size: 1.75"
Composition: AlSiCuCoFeNdB
Cobalt Cobaltite

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Cobaltite.
Description from the source:
Cobaltite (Co As S orth.), Geyer, Tyrol, Austria. Cristalline gray masses with pinkish Erytrite from a very old austrian mine. 1,5x0,8x0,8 cm; 4 g with box.
Source: Simone Citon
Contributor: John Gray
Acquired: 28 January, 2009
Text Updated: 29 January, 2009
Price: Trade
Size: 0.6"
Composition: CoAsS
Cobalt Photo Card Deck of the Elements

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Photo Card Deck of the Elements.
In late 2006 I published a photo periodic table and it's been selling well enough to encourage me to make new products. This one is a particularly neat one: A complete card deck of the elements with one big five-inch (12.7cm) square card for every element. If you like this site and all the pictures on it, you'll love this card deck. And of course if you're wondering what pays for all the pictures and the internet bandwidth to let you look at them, the answer is people buying my posters and cards decks. Hint hint.
Source: Theodore Gray
Contributor: Theodore Gray
Acquired: 19 November, 2008
Text Updated: 28 October, 2017
Price: $35
Size: 5"
Composition: HHeLiBeBCNOFNeNaMg AlSiPSClArKCaScTiVCrMn FeCoNiCuZnGaGeAsSeBrKr RbSrYZrNbMoTcRuRhPdAg CdInSnSbTeIXeCsBaLaCePr NdPmSmEuGdTbDyHoErTm YbLuHfTaWReOsIrPtAuHgTl PbBiPoAtRnFrRaAcThPaUNp PuAmCmBkCfEsFmMdNoLrRf DbSgBhHsMtDsRgCnNhFlMcLvTsOg
Cobalt Erythrite

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Erythrite.
Description from the source:
Erythrite (Co3 (AsO4)2x8 H2 O mon.), Dome Rock, South Australia, Australia. With pseudocubic Smolianinovite. 3x2,2x1,5 cm; 7 g.
Source: Simone Citon
Contributor: John Gray
Acquired: 30 October, 2008
Text Updated: 13 March, 2009
Price: Trade
Size: 0.75"
Composition: Co3(AsO4)2.8H2 O
Cobalt Carrollite

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Carrollite.
Description from the source:
Carrollite (Cu (Co Ni)2 S4 cub.), Kamoya II Mine, Shaba, Rep. Dem. of Congo. Perfect crystal on matrix. 5x4x3,2 cm; 87 g.
Source: Simone Citon
Contributor: John Gray
Acquired: 30 September, 2008
Text Updated: 1 October, 2008
Price: Trade
Size: 2"
Composition: Cu(CoNi)2S4
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!
Cobalt Arc-melted magnetic alloy

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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
Text Updated: 30 April, 2008
Price: Anonymous
Size: 1.5"
Composition: FeCo
Cobalt Manganese Nodule

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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
Cobalt Erythrite from Jensan Set

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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
The Elements book Mad Science book Periodic Table Poster  Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here!