042 Molybdenum
042 Molybdenum
040 Zirconium041 Niobium042 Molybdenum043 Technetium044 RutheniumBlankBlankBlankBlankBlankBlank024 Chromium042 Molybdenum074 Tungsten106 Seaborgium
Molybdenum steel (an alloy of iron with a few percent of molybdenum) is used extensively for machine tool bits, because it is very hard and tough. Pure, or reasonably pure (90+%), molybdenum is used for very high temperature, high pressure chemical processing equipment, because molybdenum retains great strength at high temperatures, and is impervious to many forms of chemical attack.
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Collections:
Elements in the Human Body
Samples with Rotatable Images
042.1
Small rectangle of foil 99.95%.
Kindly donated by David Franco, who sent many elements after seeing the slashdot discussion.
Source: David Franco
Contributor: David Franco
Acquired: 17 May, 2002
Price: Donated
Size: 1"
Purity: 99.95%
042.2
3DCylinder.
Purchased from Neil Lipson (Lipson@postoffice.att.net) after contact through eBay. No information on the source or use of this sample. This stuff is close to the density of lead, but much harder. It's a nice hunk.

Analysis by x-ray fluorescence spectroscopy at the Center for Microanalysis of Materials, University of Illinois (partially supported by the U.S. Department of Energy under grant DEFG02-91-ER45439) indicates that it is essentially pure molybdenum.

Source: Neil Lipson
Contributor: Theodore Gray
Acquired: 29 May, 2002
Price: $19
Size: 2"
Purity: 99.9%
042.3
3DNut and bolt, broken.
Purchased from Neil Lipson through eBay. This bolt was said to have been from a high-temperature pressure vessel of some sort. If you look at the broken surface in the high-resolution picture, you can clearly see that it's not like any steel, at least not like any I've ever seen. The melting point of molybdenum is a good 1000C higher than steel, and it's pretty strong stuff.

Analysis by x-ray fluorescence spectroscopy at the Center for Microanalysis of Materials, University of Illinois (partially supported by the U.S. Department of Energy under grant DEFG02-91-ER45439) indicates that this bolt is approximately 92% molybdenum with the remainder a mixture of cobalt and chromium.

So, in case you had any lingering doubts about whether someone would pay $13 for a broken 1/4-20 bolt on eBay, the answer is yes.
Source: Neil Lipson
Contributor: Theodore Gray
Acquired: 15 August, 2002
Price: $13
Size: 1.5"
Purity: 92%
042.4
Tiny cylinder.
Ed bought half a dozen different tiny metal cylinders from David Franco, intending to make some kind of puzzle out of them (Ed's a puzzle person). But they turned out to be too irregular, so he donated them to the table.
Source: David Franco
Contributor: Ed Pegg Jr
Acquired: 19 August, 2002
Price: Donated
Size: 0.2"
Purity: 99.98%
042.5
Sample from the Red Green and Blue Company Element 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 The Red Green & Blue Company
Contributor: Max Whitby of The Red Green & Blue Company
Acquired: 25 January, 2003
Price: Donated
Size: 0.2"
Purity: 99.9%
042.6
Sample from the Everest Element 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 (excepted gasses) weight 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%