Question

The most common ore of iron is _______________.
A) Calamine
B) Hematite
C) Zinc blende
D) Copper pyrite

Answer 1

Recall the principal ores of iron. Among all the ores of iron, two ores are highly important for the extraction of metallic iron. One of them has the appearance of reddish brown or shades of red. Ores of iron are rich in iron oxides.

Complete answer:
Ores of iron are minerals or rocks from which iron metal can be extracted. Iron is one of the most abundant metals found in the earth’s crust and it is usually combined with other elements such as oxygen and sulphur. Usually, the ores of iron are rich in oxygen or are in the form of iron oxides. These ores vary in colour as well as in composition. Now, let us enlist the principal ores of iron with their appearance, composition and the percentage of metal iron they contains:

Ores of iron	Appearance	Composition	% of Fe
Hematite	Shades of red and reddish brown	$F{e_2}{O_3}$	70-60
Magnetite	Steel grey or black	$F{e_3}{O_4}$	72-62
Limonite	Yellowish brown	$F{e_2}{O_3}.{H_2}O$	63-59
Siderite	Pale yellow to dark brown	$FeC{O_3}$	48
Iron pyrites	Dark yellow to yellowish brown	$Fe{S_2}$	46

Among all the iron ores, hematite and magnetite are the most important ores because most of the iron which is used to make steel is mined from these two ores. Hematite and magnetite ores having composition $F{e_2}{O_3}$ and $F{e_3}{O_4}$, are quite rich in metallic iron. Therefore among the given options, the most common ore of iron is hematite.

Thus, option B is correct.

Note: Most of the extracted metallic iron from its ores is used to make steel. Iron ore is the raw material used to make pig iron, which in turn is one of the main raw materials to manufacture steel. Iron is also widely used in the construction of railway tracks, roads, appliances, buildings or other infrastructures.