HISTORY
Cobalt was discovered by Georg Brandt, a Swedish
chemist, in 1739. Brandt was attempting to prove that
the ability of certain minerals to color glass blue was
due to an unknown element and not to bismuth, as was
commonly believed at the time. Cobalt's primary ores
are cobaltite (CoAsS) and erythrite (Co3(AsO4)2). Cobalt
is usually recovered as a byproduct of mining and
refining nickel, silver, lead, copper and iron.
Although cobalt is used in electroplating to give
objects an attractive surface that resists oxidation, it is
more widely used to form alloys. Alnico, an alloy
consisting of aluminum, nickel and cobalt is used to
make powerful permanent magnets. Stellite alloys,
which contain cobalt, chromium and tungsten, are used
to make high-speed and high temperature cutting tools
and dyes. Cobalt is also used to make alloys for jet
engines and gas turbines, magnetic steels and some
types of stainless steels.
Cobalt-60, a radioactive isotope of cobalt, is an
important source of gamma rays and is used to treat
some forms of cancer and as a medical tracer. Cobalt-60
has a half-life of 5.27 years and decays into nickel-60
through beta decay
Cobalt compounds have been used for centuries
to color porcelain, glass, pottery, tile and enamel. Some
of these compounds are known as: cobalt blue,
ceruleum, new blue, smalt, cobalt yellow and cobalt
green. In addition to being used as a dye, cobalt is also
important to human nutrition as it is an essential part of
vitamin B12.
(source:https://education.jlab.org/itselemental/ele027.
html)
Cobalt-60 (Co-60)
Half-life: 5.27 years
Mode of decay: Beta particles and gamma radiation
Chemical properties: Metallic solid that can become
magnetically charged
What is it used for?
Co-60 is used medically for radiation therapy as
implants and as an external source of radiation
exposure. It is used industrially in leveling gauges and to
x-ray welding seams and other structural elements to
detect flaws. Co-60 also is used for food irradiation, a
sterilization process.
Where does it come from?
Nonradioactive cobalt occurs naturally in various
minerals and has long been used as a blue coloring agent
for ceramic and glass. Radioactive Co-60 is produced
commercially through linear acceleration for use in
medicine and industry. Co-60 also is a byproduct of
nuclear reactor operations, when metal structures, such
as steel rods, are exposed to neutron radiation.
What form is it in?
Co-60 occurs as a solid material and might appear as
small metal disks or in a tube, enclosed at both ends,
that holds the small disks. Co-60 can occur as a powder
if the solid sources have been ground or damaged..
How can it hurt me?
Because it decays by gamma radiation, external
exposure to large sources of Co-60 can cause skin burns,
acute radiation sickness, or death. Most Co-60 that is
ingested is excreted in the feces; however, a small
amount is absorbed by the liver, kidneys, and bones. Co60 absorbed by the liver, kidneys, or bone tissue can
cause cancer because of exposure to the gamma
radiation. (source:https://www.cdc.gov/nceh/radiation
/emergencies/isotopes/cobalt.htm)