Cobalt "goblin", a superstitious term used for the ore of cobalt by miners. The first attempts to smelt those ores for copper or nickel failed, yielding simply powder (cobalt(II) oxide) instead. Because the primary ores of cobalt always contain arsenic, smelting the ore oxidized the arsenic into the highly toxic and volatile arsenic oxide, adding to the notoriety of the ore. Swedish chemist Georg Brandt (1694–1768) is credited with discovering cobalt circa 1735, showing it to be a previously unknown element, different from bismuth and other traditional metals. Brandt called it a new "semi-metal". He showed that compounds of cobalt metal
Element collecting Element collecting Element collecting is the hobby of collecting the chemical elements. Many element collectors simply enjoy finding peculiar uses of chemical elements. Others enjoy studying the properties of the elements, possibly engaging in amateur chemistry, and some simply collect elements for no practical reason. Some element collectors invest in elements, while some amateur chemists have amassed a large collection of elements—Oliver Sacks, for example. In recent years, the hobby has gained popularity with media attention brought by element collectors like Theodore Gray. Some collectors attempt to collect very high purity samples of each element. Others prefer to find the