Cobalt (symbol Co) is a chemical element, a ferromagnetic metal with atomic number 27 that belongs to the Group 9 of the periodic table, used especially for heat-resistant and magnetic alloys. It is a lustrous, silvery-blue metal.
Cobalt (symbol Co) is a chemical element, a ferromagnetic metal with atomic number 27 that belongs to the Group 9 of the periodic table, used especially for heat-resistant and magnetic alloys. It is a lustrous, silvery-blue metal. It is among the only three metals that are known to be ferromagnetic at room temperature, other two being iron (Fe) and nickel (Ni). Though cobalt compounds had been used for centuries to impart a blue colour to glazes and ceramics but the metal itself was isolated only in 1735 by Swedish chemist Georg Brandt.
Cobalt makes up only 0.001 percent of Earth’s crust. In animals, cobalt is a trace element considered essential in the nutrition of ruminants (cattle, sheep) and in the maturation of human red blood cells in the form of vitamin B12, the only vitamin known to contain such a heavy element.
Two allotropes of cobalt are known: the hexagonal close-packed structure, stable below 417 °C (783 °F), and the face-centred cubic, stable at high temperatures. It is ferromagnetic up to 1,121 °C (2,050 °F, the highest known Curie point of any metal or alloy) and may find application where magnetic properties are needed at elevated temperatures. Cobalt, like iron, can be magnetised and so is used to make magnets. It is alloyed with aluminium and nickel to make particularly powerful magnets. Other alloys of cobalt are used in jet turbines and gas turbine generators, where high-temperature strength is important. Cobalt metal is sometimes used in electroplating because of its attractive appearance, hardness and resistance to corrosion. Radioactive cobalt-60 is used to treat cancer and, in some countries, to irradiate food to preserve it.
In this immersive teacher training, you will be introduced to the concepts of geometry from our ancient history to the application in modern science. By understanding geometry, we will decode the philosophical meaning behind many universal symbols and reveal how they are linked together in an artistic way.