Cobalt for "goblin ore") for some of the blue-pigment producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the "kobold". Today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as for example cobaltite (CoAsS). The element is however more usually produced as a by-product of copper and nickel mining. The copper belt in the Democratic Republic of the Congo
Isotopes of cobalt an excited state of the Fe nucleus, which in turn decays to the ground state with emission of a gamma ray. Measurement of the gamma ray spectrum provides information about the chemical state of the iron atom in the sample. Isotopes of cobalt Naturally occurring cobalt (Co) is composed of 1 stable isotope, Co. 28 radioisotopes have been characterized with the most stable being Co with a half-life of 5.2714 years, Co with a half-life of 271.8 days, Co with a half-life of 77.27 days, and Co with a half-life of 70.86 days. All of the remaining radioactive isotopes have