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Cobalt is a grayish, hard, brittle metal closely resembling iron and nickel. These three metals are the only naturally magnetic elements on Earth. Cobalt exists in two allotropic forms that interconvert slowly. This property accounts for the fact that...

Cobalt is a transition metal, one of the elements that occurs in the middle of the periodic table, between Groups 2 and 13. It is located between iron and nickel, with whom it shares many common properties. Cobalt's atomic number is 27, its atomic mass...

Cobalt Symbol Co Atomic Number 27 Atomic Mass 58.9332 Family Group 9 (Viiib) Transition Metal Pronunciation CO-balt Overview Humans have been using compounds of cobalt since at least 1400 B.C. The compounds were used to color glass and glazes blue. In...

Cobalt (pronounced /ˈkoʊbɒlt/) is a hard, lustrous, silver-grey metal, a chemical element with symbol Co. It is found in various ores, and is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Its compounds are used in the...

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The Energy Department has not done enough in Russia and in developing countries to secure radioactive material that could be used to make a so-called dirty bomb, congressional investigators said Tuesday.A report by the Government Accountability Office said that over the past four years security...

The Energy Department has not done enough in Russia and in developing countries to secure radioactive material that could be used to make a so-called dirty bomb, congressional investigators said Tuesday.A report by the Government Accountability Office said that over the past four years security...

The Energy Department has not done enough in Russia and in developing countries to secure radioactive material that could be used to make a so-called dirty bomb, congressional investigators said.A report released Tuesday by the Government Accountability Office said that over the past four years...