(So named (German kobold, literally "goblin", term used for the ore by miners, who regarded it as worthless and injurious because of its arsenic content) circa 1730 by Georg Brandt, Swedish chemist) A hard, lustrous, steel-gray, ductile, metallic chemical element, found in various ores. It is used in the preparation of magnetic, wear-resistant, and high-strength alloys. It's compounds are used in the production of inks, paints, and varnishes

Symbol: Co
Atomic number: 27
Atomic weight: 58.933200
Density (at room temperature and pressure): 8.9 g/cc
Melting point: 1,495°C
Boiling point: 2,927°C
Valence: +2, +3
Ground state electron configuration: [Ar]3d74s2

See also: cobalt-60
Symbol: Co
Atomic Number: 27
Boiling Point: 3143 K
Melting Point: 1768 K
Density at 300K: 8.90 g/cm3
Covalent radius: 1.16
Atomic radius: 1.67
Atomic volume: 6.70 cm3/mol
First ionization potental: 7.86 V
Specific heat capacity: 0.421 Jg-1K-1
Thermal conductivity: 100 Wm-1K-1
Electrical conductivity: 17.9 106Ω-1m-1
Heat of fusion: 16.19 kJ/mol
Heat of vaporization: 373.3 kJ/mol
Electronegativity: 1.88 (Pauling's)

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To the Periodic Table

A small town in northern Ontario, Cobalt is one of the Tri-Towns, and it's had the most spectacular fall from grace of the bunch.

In 1903, silver and cobalt (hence the name) were discovered here in great abundance. The story is that a blacksmith threw a hammer at a red fox hanging around his forge, missed the fox and hit silver instead. Nearly overnight, as the saying goes, the town went from sleepy little hamlet to great bustling huge get-rich-quick mining town. There were huge amounts of money made here. From Stephen Leacock:

"...presently young Fizzlechip, who had been a teller in Mullin's Bank and that everybody had thought a worthless jackass before, came back from the Cobalt country with a fortune, and loafed around in the Mariposa House in English khaki and a horizontal hat, drunk all the time, and everybody holding him up as an example of what it was possible to do if you tried."
  --Sunshine Sketches of a Little Town, by Stephen Leacock

Of course, the boom ran out eventually, and most people went away. The town was left criss-crossed and riddled with abandoned mine tunnels. Records-keeping wasn't a priority. Every now and then someone -- usually a kid -- would wander into one of them and never come out. And then there was The World's Biggest Pothole.

Highway 11 used to go right through Cobalt -- wound right through it just like a snake trying to make a point about flexibility -- and on to Haileybury and New Liskeard. That was before the more direct route was built that went straight through to New Liskeard; the section that went through Cobalt was renamed 11B, "The Scenic Route," and fooled few.

Anyway, the Pothole. One day, 11B just collapsed right in the middle of town. The polite word was "subsidence", but no one used that but the Reeve. The hole was something like 60 feet deep; I don't know how far across it was. The mining tunnels had taken their revenge something fierce. Bus drives through town now took an extra ten or fifteen minutes through us, and included some decidedly rural areas, as we navigated the already-rivaling-San-Francisco-in-their-windiness streets of Cobalt without The Highway.

This, at least, was something to look at in Cobalt. I don't want to be mean, but there really wasn't much. There was a mineral museum there -- the display of florescent materials its high point -- and then a selection of The World's Biggest Pothole T-shirts. Other than that there was the Sears outlet, the post office, a few taverns and the CIBC that held the mortgage on the first house my parents bought. (It was in Temagami, but the CIBC was my parents' bank and Cobalt its closest branch.)

Cobalt is trying to make itself a tourist attraction, and for all I know may be doing quite well; I haven't been back in more than ten years. But I remember that in high school, when everyone who wasn't from the bustling metropoli of Haileybury and New Liskeard was made fun of, no one bothered picking on Cobalt. You didn't mock the dead.

Co"balt [G. kobalt, prob. fr. kobold, kobel, goblin, MHG. kobolt; perh. akin to G. koben pigsty, hut, AS. cofa room, cofgodas household gods, Icel. kofi hut. If so, the ending -old stands for older -walt, -wald, being the same as -ald in E. herald and the word would mean ruler or governor in a house, house spirit, the metal being so called by miners, because it was poisonous and troublesome. Cf. Kobold, Cove, Goblin.]

1. Chem.


⇒ It occurs in nature in combination with arsenic, sulphur, and oxygen, and is obtained from its ores, smaltite, cobaltite, asbolite, etc. Its oxide colors glass or any flux, as borax, a fine blue, and is used in the manufacture of smalt. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron.


A commercial name of a crude arsenic used as fly poison.

Cobalt bloom. Same as Erythrite. -- Cobalt blue, a dark blue pigment consisting of some salt of cobalt, as the phosphate, ignited with alumina; -- called also cobalt ultramarine, and Thenard's blue. -- Cobalt crust, earthy arseniate of cobalt. -- Cobalt glance. Min. See Cobaltite. -- Cobalt green, a pigment consisting essentially of the oxides of cobalt and zinc; -- called also Rinman's green. -- Cobalt yellow Chem., a yellow crystalline powder, regarded as a double nitrite of cobalt and potassium.


© Webster 1913.
