Cobalt are faced by cobalt miners. Cobalt can be effectively absorbed by charred pigs' bones; however, this process is inhibited by copper and zinc, which have greater affinities to bone char. Cobalt Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal. Cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a
Period 4 element in period 4, between chromium and iron. Manganese is often found free in nature, but is also found in combination with iron. Manganese, like chromium before it, is an important component in stainless steel, preventing the iron from rusting. Manganese is also often used in pigments, again like chromium. Manganese is also poisonous; if enough is inhaled, it can cause irreversible neurological damage. Iron (Fe) is an element in period 4, between manganese and cobalt. Iron is probably the most well-known element in period 4, being the most common element in the earth and a major component of steel. Iron-56