Cobalt (so named from the Greek for goblin, a demon of the mines) is a greyish-white coloured metal element with the symbol Co. It was discovered among the ore veins in Cornwall in early times and called mundic by the miners. It was identified as a metal in 1733 by Brandt. Cobalt is very brittle, of a fine close grain, compact, but easily reducible to powder. It crystallizes in parallel bundles of needles. It is never found in a pure state, but usually as an oxide, or combined with arsenic or its acid, with sulphur, iron, etc.
Its ores are arranged under the following species: arsenical cobalt, of a white colour, passing to steel grey; its texture is granular, and when heated it exhales the odour of garlic; gray cobalt, a compound of cobalt, arsenic, iron, and sulphur, of a white colour, with a tinge of red; its structure is foliated, and its crystals have a cube for their primitive form; sulphide of cobalt, compact and massive in its structure; oxide of cobalt, brown or brownish black, generally friable and earthy; sulphate and arsenate of cobalt, both of a red colour, the former soluble in water. The great use of cobalt is to give a permanent blue colour to glass and enamels upon metals, porcelain, and earthenwares. Research Cobalt
Annabergite (also known as nickel bloom) is a rare secondary mineral of a pale green colour, that forms in the oxidation zones of ore deposits and is found as a powdery coating on the surface of nickel-bearing minerals such as chloanite and nickeline. Annabergite is a hydrated arsenate of nickel of the vivanite group. Research Annabergite
Carminite is an arsenate mineral of a striking red colour formed in veins of iron and lead ore. Carminite was identified as a distinct mineral in 1850.
Carminite is a readily soluble compound of arsenic acid, oxygen, lead and iron. Research Carminite
Ceruleite is a sky-blue coloured arsenate mineral similar in appearance and hardness to turquoise first discovered in the Emma Louisa gold mine in Huanaco, Chile and confirmed as a distinct mineral in 1900. Research Ceruleite
Olivenite is a rare olive-green, brown or yellow coloured secondary mineral found in deeply weathered, highly concentrated copper sulphide ore bodies. It is a hydrous arsenate of copper confirmed as a distinct species in 1820 and sometimes mined as a copperore. Olivenite has a relative hardness of 3. Research Olivenite
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Matt and Leela Probert
Abbreviations
Research Cobalt
