Here is a litte piece I ran into while looking for another doc right now. It does not delve deeply in to the science of how it can be used for pigmentation, but does list it's uses and some history info on it. The latter part of the document should explain why it may not be easily accessed or readily dissimenated information. The three companies I emailed have not repsonded. I will emailthem again and tryo calling. They might be leary, due to some uses of cobalt, to respond to emails from folks they do not know. That is probably about as in detail as I will get on this thread. When I get a response from a proper scientific authority I will let you know what they say. If this thread dies in that time I will start another. I just want to wait until I have something that is stated wisely and is not going to present any sort of problems or idea theft.
Notable characteristics
Cobalt is a hard
ferromagnetic silver-white element. The
Curie temperature is of 1388 K with 1.6~1.7
Bohr magnetons per
atom. It is frequently associated with
nickel, and both are characteristic ingredients of meteoric iron.
Mammals require small amounts of cobalt
salts. Cobalt-60, an artificially produced
radioactive isotope of cobalt, is an important radioactive tracer and
cancer-treatment agent. Cobalt has a relative permeability two thirds that of iron.
Metallic cobalt commonly presents a mixture of two crystallographic structures hcp and
fcc with a
transition temperature hcp->fcc of 722 K.
Common oxidation states of cobalt include +2, and +3, though +1 is also seen.
Applications Co-60 is useful as a gamma ray source partially because it can be produced - in known quantity, and very large amounts - by simply exposing natural cobalt to
neutrons in a reactor for a given time.
Use in medicine
Cobalt-60 (Co-60 or 60Co) is a
radioactive metal that is used in
radiotherapy. It produces two gamma rays with energies of 1.17
MeV and 1.33 MeV. The 60Co source is about 2
cm in diameter and as a result produces a
geometric penumbra, making the edge of the
radiation field fuzzy. The metal has the unfortunate habit of producing a fine dust, causing problems with radiation protection. The 60Co source is useful for about 5 years but even after this point is still very radioactive, and so cobalt machines have fallen from favor in the Western world where
linacs are common. The first 60Co therapy machine (the "
cobalt bomb") was built and first used in
Canada. In fact the first machine is on display in the
Saskatoon Cancer Centre – look up when entering the lobby. The second machine is out beside the walkway into the Centre.
History
Cobalt was known in ancient times through its compounds, which would color
glass a rich blue.
George Brandt (1694-1768) is credited with the discovery of cobalt. The date of discovery varies depending on the source, but is between
1730 and
1737. He was able to show that cobalt was the source of the blue color in glasses, which previously had been attributed to the bismuth found with cobalt.
During the
19th century, cobalt blue was produced at the Norwegian Blaafarveværket (70-80 % of world production), led by the Prussian industrialist
Benjamin Wegner.
In 1938, John Livingood and
Glenn Seaborg discovered cobalt-60.
The word cobalt comes from the German
kobalt or
kobold, meaning evil spirit, the metal being so called by miners, because it was poisonous and troublesome (it
polluted and degraded the other mined elements, like
nickel).
Biological role
Cobalt in small amounts is essential to many living
organisms, including
humans. Having 0.13 to 0.30
parts per million of cobalt in soils markedly improves the health of
grazing animals. Cobalt is a central component of the
vitamin cobalamin, or
vitamin B-12.
Occurrence Missing image Cobalt_OreUSGOV.jpg Cobalt ore
Cobalt is not found as a free metal and is generally found in the form of
ores. Cobalt is usually not mined alone, and tends to be produced as a by-product of nickel and
copper mining activities. The main ores of cobalt are cobaltite,
erythrite, glaucodot, and
skutterudite. The world's major producers of cobalt are
DRC,
mainland China,
Zambia,
Russia and
Australia.
Compounds
Due to the various
oxidation states, there is an abundant number of compounds. Oxides are
antiferromagnetic at low
temperature] CoO (
Neel temperature: 291 K) and Co3O4 (Neel temperature: 40 K).
Isotopes
Naturally occurring cobalt is composed of 1 stable
isotope, 59-Co (59Co). 22
radioisotopes have been characterized with the most stable being 60Co with a
half-life of 5.2714 years, 57-Co (57Co) with a half-life of 271.79 days, and 56-Co (56Co) with a half-life of 77.27 days, and 58-Co (58Co) with a half life of 70.86 days. All of the remaining
radioactive isotopes have half-lifes that are less than 18 hours and the majority of these have half lives that are less than 1 second. This element also has 4
meta states, all of which have half lives less than 15 minutes.
The isotopes of cobalt range in
atomic weight from 50
amu (50Co) to 73 amu (73Co). The primary
decay mode before the most abundant stable isotope, 59Co, is
electron capture and the primary mode after is
beta decay. The primary
decay products before 59Co are element 26 (
iron) isotopes and the primary products after are element 28 (
nickel) isotopes.
Precautions
Powdered cobalt in metal form is a fire hazard. Cobalt compounds should be handled with care due to cobalt's slight toxicity.
Cobalt-60 is a powerful gamma ray emitter and exposure to 60Co is therefore a cancer risk. Ingestion of 60Co will lead to incorporation of some cobalt into tissues, which is released very slowly. Cobalt-60 is a risk factor in a nuclear confrontation because neutron emissions will convert iron into this isotope. Some
nuclear weapon designs could intentionally increase the amount of Cobalt-60 dispersed as
nuclear fallout – this is sometimes called a
dirty bomb or
cobalt bomb. The risk in the absence of a
nuclear war comes from improper handling (or theft) of medical radiotherapeutic units.
12-09-2005
Quote: 
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