Cobalt Deposits

©2010 Dr. B. C. Paul

Special Acknowledgement given to www.mindat.org, www.webmineral.com,www.minerals.net,

As Veins Above Intrusives

Black-BirdCopper CobaltDeposits

Often High Temperature Hydrothermal vein deposits

Cobaltite

CoAsS 35.5% Cobalt

Color Redish Silver White, Violet SteelGray, Grayish BlackHardness 5.5S.G. 6.33Non FluorescentMagnetic after heating Streak grayish black

Cobaltite Locations

Skutterudite

(Co,Ni)As2.5 Solid Solution – about 18% CobaltColor White, Light Silver GrayHardness 5.5-6S.G. 6.5Non Fluorescent Non MagneticStreak Black

Known Mine Occurrences

Also found with gold and silver arsenites

Arsenopyrite

An Iron, Arsenic Sulfide usually found with SkutteruditeFeAsSHardness 5 SG 6.07 Color Tin white, Light steel gray Non FluorescentMagnetic after heatingStreak Black

Zambian Copper Belt(Hydrothermal Introduction)

Carrollite

Cu(Co,Ni)2S4 28.5% Cobalt 20.5% Copper

Color Bright SilverHardness 4.5-5.5S.G. 4.8Non Magnetic Non Fluorescent Streak Gray Black

Known Mine Occurrences

SPHAEROCOBALTITE

CoCO3 49.5% Cobalt

Color Gray Brown, Pink, Black, Rose RedHardness 3-4S.G. 4.1Non Magnetic Non Fluorescent Streak Pink

Cobalto Calcite

Part of a solid solution where cobalt andCalcite trade off in the carbonate

Erythrite

Co3(AsO4)2•8(H2O) 29.53% CoHardness 1.5-2 Color Colorless, Violet red, Light pink, Purple red. SG 3.12Non Magnetic Non FluorescentStreak pinkish red

Glaucodot

(Co,Fe)AsS 26.76% CobaltColor Grayish tin white, Reddish silver white. Hardness 5SG 5.95Non FluorescentNon MagneticStreak Black

Cobalt Processing

• Cobalt is a Coproduct or Byproduct– Coproduct is where two minerals make the ore worth

while– Byproduct is where you would never mine an ore for

something, but while you are processing it is worth while to get the other ingrediant.

– Almost no ore is ever valuable for cobalt alone– Cobalt also is similar enough to copper and nickel that

it likes to stay with them in processing– Variety of ways by which cobalt can be separated.

Copper-Cobalt Sulfides

• Grind the Ore• Use Flotation to produce a concentrate of sulfide

minerals• Roast the concentrates to make oxides• Acid Leach the oxides• Precipitate out the iron and aluminum• Electrowin out the copper• Selectively precipitate out Copper, Nickel and Zinc• Finally add lime to produce cobalt hydroxide• Re-dissolve the cobalt hydroxide• Electrowin the cobalt from solution

What is Cobalt Used For?

Cobalt Uses

49

9

15

27Alloys/ AircraftEngines

Cutting Tools

Other Metals

Chemical

What Do We Have for Reserves

Metric Tonnes of Cobalt

0

20000

40000

60000

80000

Production Reserves/50

Other

Zambia

Russia

New Caledonia

Morocco

Cuba

Congo

China

Canada

Brazil

Australia

United States

What is Cobalt Worth

Cobalt Price

0

20

40

60

80

1900

1912

1924

1936

1948

1960

1972

1984

1996

2008

2009$ PerPound

Is running around $19 to $20 in 2010