Cobalt

Rare card · No. 23681

Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a 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, somewhat brittle, gray metal. Cobalt-based blue pigments (cobalt blue) have been used since antiquity for jewelry and paints, and to impart a distinctive blue tint to glass. The color was long thought to be due to the metal bismuth. The name cobalt derives from a type of ore considered a nuisance by 16th-century German silver miners, which in turn may have been named from a spirit or goblin held superstitiously responsible for it; this spirit is considered equivalent to the kobold (a household spirit) by some, or categorized as a gnome (mine spirit) by others. Today, cobalt is usually produced as a by-product of copper and nickel mining, but sometimes also from one of a number of metallic-lustered...

Read on Wikipedia · Image Alchemist-hp (talk) (www.pse-mendelejew.de), FAL