The fourth element on the periodic table, beryllium, with a chemical symbol of Be and
atomic weight of 9.01218 g/mole, is a naturally occurring substance. It is found in nature
as a solid with a density of 1.85 g/ml. Naturally, it occurs in the mineral beryl as a salt and
not in its metallic form. It is a toxic, carcinogenic substance with many uses in
technology. The element also has a sweet taste but due to the toxicity, taste is certainly
not the way to check for beryllium in a sample of ore. (1)
According to the Mineral Information Institute (MII), a French scientist, Nicholas Louis
Vauquelin, discovered beryllium around 1798. It was not isolated into its metallic form
for some time. Some semi-precious stones found in ore as forms of beryllium including
aquamarine and emerald. (1)
Found in ore, beryllium contaminates drinking water if there is a high level in the ground.
Accor dining to the Environmental Protection Agency (EPA), higher than acceptable
contaminant levels could lead to intestinal lesions. In addition to leaching from the
ground, beryllium becomes an environmental factor when coal is burned and it enters the
air through the smoke and other industrial releases. (2)
With all the contrite information being given, one must wonder what good this element
is. To the scientific community and technological world, it is a very useful substance.
One amazing attribute of beryllium that makes it so special is its very high modulus or
elasticity. It is much more elastic that steel but just as hard. (3) Just as interesting is the
high melting point of 1278 degrees Celsius as compared to around 1370 degrees Celsius
for steel. (4) Also, it is often fabricated into non-sparking tools, electrical contacts, after
it is made into an alloy with copper. Additionally, it is used for in aerospace technology
as well as in nuclear reactors.
Perhaps one of the most widely used, and most fascinating, fabrications of the substance
is into a thin-film form. The film is then used in making in the windows of x-ray
fluorescence (XRF) spectrometer tubes. The window is generally anywhere from fifty to
one hundred and twenty microns thick and is for the escape of the generated x-ray energy
particles which then can go to the sample and then to a detector. This allows for
excellent qualitative and quantitative analyses of many elements in the laboratory. This
is used routinely on samples ranging from cement to plastics. As previously mentioned,
the beryllium is toxic and carcinogenic; therefore the x-ray tube itself is very difficult to
dispose of. There are facilities equipped to handle and dispose of the tubes and it is
imperative that the tubes go to those facilities rather than merely being placed in landfills.
(5)
(1) http://www.mii.org/Minerals/photoberyl.html
(2) http://www.epa.gov/ogwdw/contaminants/dw_contamfs/berylliu.html
(3) http://chemistry.about.com/od/elementfacts/a/beryllium.htm
(4) http://education.jlab.org/qa/meltingpoint_01.html
(5) http://en.wikipedia.org/wiki/XRF
