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
Cobalt ruins of Pompeii, destroyed in 79 AD, and in China, dating from the Tang dynasty (618–907 AD) and the Ming dynasty (1368–1644 AD). Cobalt has been used to color glass since the Bronze Age. The excavation of the Uluburun shipwreck yielded an ingot of blue glass, cast during the 14th century BC. Blue glass from Egypt was either colored with copper, iron, or cobalt. The oldest cobalt-colored glass is from the eighteenth dynasty of Egypt (1550–1292 BC). The source for the cobalt the Egyptians used is not known. The word "cobalt" is derived from the German "", from "kobold" meaning