Metals and Ores For PSC

Metals and Ores For PSC

Ores are naturally occurring materials that may be mined to extract a mineral or minerals of commercial worth. Minerals, particularly metals, are often mined in ore form first, then processed.

Ore is derived from the combination of two Old English words: Ora, which means 'unworked metal,' and ar, which means 'brass, copper, or bronze.'

Oxides and sulphides are the most prevalent metal ores. 

Sulphides are the earliest ores, having developed when there was a lot of sulphur in the Earth's past due to volcanic activity. Later, when photosynthesis in plants released significant amounts of oxygen into the atmosphere, oxides developed.

Iron ore is the most prevalent element on the planet, accounting for over 5% of the Earth's crust. As a result, it is one of the most plentiful rock components.

Metals and their ores are an important topic that is included in the syllabus of the upcoming 10th preliminary and other preliminary and main exams of Kerala PSC.

Metals and Ores


The table below covers some of the most important metals, as well as their ores and chemical formulae. You can use the search function below to look for a certain metal and its ore.


MetalOreChemical Formula
Aluminium
(Al)
Bauxite

Corundum

Cryolite

Feldspar

Alunite

Kaolin (clay)
Al₂O₃ 2H₂O

Al₂O₃

Na₃AlF₆

KAlSi₃O₈

KAl₃(SO4)2(OH)₆.

Al₂O₃ 2SiO₄·2H₂O 
Antimony (Sb)StibniteSb₂S₃
Barium (Ba)BarytesBaSO₄
Beryllium (Be)BerylBe₃Al₂Si₆O₁₈
Bismuth (Bi)BismuthateBiO₃
Cadmium (Cd)Greenockite

CdS

Calcium (Ca)Dolomite

Limestone

Calcite

Gypsum

Fluorspar/Fluorite

Asbestos

Kaolinite
(a form of clay)
MgCO₃CaCO₃

CaCO₃

CaCO₃

CaSO₄⋅ 2H₂O

CaF2

CaMg₃(SiO₃​)₄

Al₂O₃ 2SiO₂·2H₂O
Chromium (Cr)Chromite(Fe, Mg)Cr₂O₄
Cobalt (Co)Cobaltite

Smelite
CoAsS

CoAsS₂
Copper (Cu)Cuprite

Malachite

Bornite / 
Peacock Ore

Chalcocite

Copper pyrites

Copper glance
Cu₂H₂O

Cu₂CO₃(OH)₂

Cu₅FeS₄

Cu₂S

CuFeS₂

Cu2S
Gold (Au)Calaverite

Sylvanite
AuTe₂

(Ag,Au)Te₂
Iron (Fe)Haematite

Magnetite

Siderite

Iron pyrites

Limonite
Fe₂O₃

Fe3O4

FeCO₃

FeS₂

FeO·nH₂O
Lead (Pb)Galena

Anglesite
PbS

PbCl₂
Manganese
(Mn)
Pyrolusite

Manganate 
MnO₂

MnO₄
Magnesium
(Mg)
Magnesite

Dolomite

Epsom salt/
Magnesium sulfate

Kieserite

Carnallite
MgCO₃

MgCO₃·CaCO₃

MgSO₄

MgSO₄·H₂O

KMgCl₃·6(H₂O)
Mercury (Hg)Calomel

Cinnabar
Hg₂Cl₂

HgS
Nickel (Ni)Pentlandite

Milarite
(Fe, Ni)₉S₈

K₂Ca₄Al₂Be₄Si₂₄O₆₀ · H₂O
Potassium
(K)
Nitre/
Saltpetre

Carnalite
KNO₃

KClMgCl6H2O
Phosphorous (P)Floreopetite3Ca₃(PO₄)CaFe₂

PhosphoriteCa₃(PO₄)CaFe₂
Tungsten (W)Wolframite

Scheelite
(Fe, Mn)WO₄

CaWO₄
Silver (Ag)Argentite

Ruby silver / 
Pyrargyrite

Horn silver / 
Chlorargyrite
Ag₂S

Ag₂S⋅Sb₂S₃

AgCl
Sodium
(Na)
Chile saltpetre

Trona

Borax

Common salt
NaNO₃

Na₃H(CO₃)₂·2H₂O

Na₂[B₄O₅(OH)₄]·8H₂O

NaCl

Strontium (Sr)Strontianite
SrCO₃
Uranium (U)Carnotite

Pitchblende /
Uraninite
K₂(UO₂)₂(VO₄)₂3H₂O

UO₂
Zinc (Zn)Zinc blend/Sphalerite

Calamine

Zincite
ZnS

ZnCO₃

ZnO

Extraction of Ores

The process of extracting metals from their ores and purifying them is called Metallurgy. The process utilised to extract a certain metal from its ore is determined by the metal's reactivity and hence the ore's stability.

The main three steps involved in metallurgy are:
  1. Ore Concentration.
  2. Metal extraction from concentrated ore.
  3. The purification of the metal.
Gangue/matrix refers to the undesired impurities and earthy things found in the ore, such as sand, limestone, and rocky materials. Flux is a chemical that is applied to ore to eliminate impurities. Slag is formed when gangue and flux in ores combine to generate a fusible substance.

The process of extracting gangue from the ore is determined by the ore's physical and chemical qualities.

For example: Aluminium.

Aluminium is one of the most abundant elements in the Earth's crust, and it may be found in a variety of silicate ores, which are frequently a type of clay.

Bauxite is an ore of aluminium. Two techniques are used to extract aluminium from bauxite ore industrially. They are as follows:
  1. Bayer Process: It refines bauxite ore (through concentrated sodium hydroxide) to generate alumina (aluminium oxide) and the remainder is a combination of silica, different iron oxides, and titanium dioxide (gangue).
  2. Hall–HĂ©roult Process: It involves the smelting of aluminium. The alumina (aluminium oxide) produced by the Bayer method then is electrolyzed with molten cryolite and feldspar to produce pure aluminium.

Thanks for reading!!!