Metals and Metallurgy – Vocabulary Flashcards

A comprehensive set of vocabulary flashcards covering key terms related to metals, their ores, and metallurgical processes, designed for efficient exam review.

Metal

A generally positive element that is hard, malleable, ductile, lustrous, sonorous and a good conductor of heat and electricity.

Mineral

Naturally occurring material containing a metal or its compound, mixed with unwanted gangue.

Ore

A mineral from which a metal can be economically and conveniently extracted.

Gangue (Matrix)

Unwanted earthy or rocky impurities present in an ore.

Oxide Ore

Ore in which a metal occurs in oxidised form, e.g., haematite for iron, bauxite for aluminium.

Sulphide Ore

Ore in which a metal is present as a sulphide, e.g., zinc blende (ZnS), galena (PbS).

Sulphate Ore

Ore containing sulphate ions, e.g., anglesite (PbSO₄).

Carbonate Ore

Ore containing carbonate ions, e.g., calcite (CaCO₃).

Alloy

Homogeneous mixture of a metal with at least one other metal or non-metal, e.g., brass, bronze, steel.

Haematite

Fe₂O₃; chief oxide ore of iron (~75 % iron).

Magnetite

Fe₃O₄; magnetic oxide ore of iron.

Siderite

FeCO₃; carbonate ore of iron.

Limonite

Fe₂O₃·3H₂O; hydrated oxide ore of iron.

Iron Pyrite

FeS₂; sulphide mineral popularly called ‘fool’s gold’.

Bauxite

Al₂O₃·2H₂O; chief ore of aluminium (40–60 % Al).

Feldspar

KAlSi₃O₈; silicate mineral containing aluminium.

Corundum

Al₂O₃; hard oxide mineral of aluminium.

Cryolite

Na₃AlF₆; fluoride ore of aluminium.

Alum Stone (Alunite)

KAl(SO₄)₂·12H₂O; hydrated sulphate mineral of aluminium.

Kaolin (China Clay)

Al₂O₃·2SiO₂·2H₂O; aluminium silicate clay mineral.

Chalcopyrite

CuFeS₂; chief sulphide ore of copper (34.64 % Cu).

Chalcocite

Cu₂S; copper sulphide ore also called copper glance.

Cuprite

Cu₂O; oxide ore of copper.

Malachite

Cu₂CO₃(OH)₂; basic carbonate ore of copper.

Argentite

Ag₂S; chief sulphide ore of silver (~87 % Ag).

Horn Silver

AgCl; chloride ore of silver.

Ruby Silver (Pyrargyrite/Polybasite)

Ag₂Sb₂S₃; antimony–silver sulphide ore.

Gold (noble metal)

Highly unreactive metal occurring free in alluvial deposits and quartz veins; symbol Au.

Calaverite

AuTe₂; telluride ore of gold.

Metallurgy

Science and technology of extracting and refining metals from their ores.

Mining

Process of removing minerals and useful substances from the earth’s crust.

Crushing

Mechanical breaking of large ore pieces into smaller lumps using crushers.

Pulverisation (Grinding)

Further reduction of crushed ore to fine powder using ball or stamp mills.

Concentration (Dressing)

Process of removing gangue to enrich the ore before extraction.

Hand Picking

Manual removal of large, visibly different impurities from an ore.

Gravity (Hydraulic) Separation

Concentration method using density difference; heavier ore settles, lighter gangue is washed away.

Froth Flotation

Concentration of sulphide ores by attaching hydrophobic ore particles to froth while gangue remains below.

Magnetic Separation

Removal of magnetic impurities or ores using a moving belt over magnetic rollers.

Leaching

Chemical dissolution of ore in a suitable solvent to separate it from insoluble impurities.

Oxidation (in Metallurgy)

Heating concentrated ore below melting point to form metal oxides; achieved by calcination or roasting.

Calcination

Strong heating of carbonate/hydroxide ores in limited or no air to form oxides and remove volatiles.

Roasting

Strong heating of sulphide ores in excess air to convert them into oxides and release SO₂.

Reduction

Conversion of metal oxides to free metals using reducing agents like carbon, CO, or H₂.

Smelting

Strong heating of oxide ore with reducing agent and flux to obtain molten metal.

Flux

Substance added during smelting to react with gangue, forming an easily fusible slag.

Slag

Fusible mass produced when flux combines with gangue during smelting.

Distillation (Metal Refining)

Refining method where volatile metal or impurity is evaporated and re-condensed to separate it.

Electrolytic Refining

Purification of a metal by making impure metal the anode and pure metal strip the cathode in electrolysis.

Anode Mud

Impurity residue collecting beneath the anode during electrolytic refining.