Cobalt canyon in the side of a mountain. The firm Calera Mining Company started production at the site. The stable form of cobalt is produced in supernovas through the r-process. It comprises 0.0029% of the Earth's crust. Free cobalt (the native metal) is not found on Earth because of the oxygen in the atmosphere and the chlorine in the ocean. Both are abundant enough in the upper layers of the Earth's crust to prevent native metal cobalt from forming. Except as recently delivered in meteoric iron, pure cobalt in native metal form is unknown on Earth. The element has a medium
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