Occurrence of Metals - Minerals, Ores, Abundance and Uses of Metals, Metallurgy, Practice Problems and FAQ

Metals have altered the way human civilisations have flourished. The three metal ages dominate the timeline of early human civilisations. They are

Iron Age
Copper Age
Bronze Age

The ability to extract metals from their ores gave rise to the creation of weapons, tools, ornaments, utensils, etc.

The copper ore used to make the objects were extracted from chalcopyrite ore deposits in the Aravalli Hills. The Archaeological Survey of India has compiled and published a collection of archaeological texts from copper plates and rock inscriptions over the last century. Copper plates were used to engrave royal records (Tamra-patra). The oldest known copper plate contains a Mauryan record mentioning famine relief efforts. It contains one of India's few pre-Ashoka Brahmi inscriptions.

In this concept page, we will study the ores and minerals of different metals, their abundance and their uses in detail.

TABLE OF CONTENTS

Introduction
Minerals
Ores
Classification of Ores
Abundance of Metals
Pricicpal Ores of Some Metals
Metallurgy
Uses of Metals
Practice Problems
Frequently Asked Questions - FAQ

Introduction

Elements in Earth’s crust occur in free as well as in the combined state. Elements like noble gases, etc., occur in pure state. On the other hand, elements like , etc., occur as oxides, halides, sulphides, etc. Generally, the metals occurring in the combined state involve various processes for their extraction and isolation.

Minerals

Any compounds of metal which are naturally available in Earth’s crust and can be obtained by mining are said to be minerals.

Example: (Iron pyrite)

Ores

The minerals from which a metal can be extracted economically and conveniently are referred to as ores. They are usually contaminated with earthly and undesired substances known as gangue.

Classification of Ores

Based on their occurrence, ores are classified into two types namely, native and combined state.

1. Native Ores: These are the metals that occur in their natural state or free state in nature. Ores of metals like silver, gold, platinum, are commonly found in pure state.

2. Combines Ores: These are the metals that occur in form of their carbonates, phosphates, sulphates, and silicates in nature. These are the reactive metals like aluminium, zinc, iron, Potassium, sodium, calcium, magnesium, lead etc.

Abundance of Metals

Among all the metals, aluminium is the most abundant. It is the major component of igneous minerals including mica and clays.

Metal	Percentage Abundance
Aluminium	8.23%
Iron	5.63%
Calcium	4.15%
Sodium	2.36%
Magnesium	2.33%
Potassium	2.09%
Titanium	0.565%
Copper	0.006%
Zinc	0.007%
Nickel	0.0084%
Gold	0.000004%
Silver	0.0000075%
Platinum	0.0000005%
Palladium	0.0000015%

Principal Ores of Some Metals

Metallurgy

Metallurgy is the subject that deals with the science and technology for the extraction of metals economically. Given below is the flowchart for all the steps involved in the isolation of metal from its ore.

Uses of Metals

Iron: Iron is one of the essential elements in biological systems like Haemoglobin. It is used in daily life in tools, machinery, as well as vehicles, structural elements for buildings, hulls of ships, bridges, and aircraft.

Cast iron is a hard and brittle iron and carbon alloy with a higher carbon content than steel (usually 2–4.3%). Pipes, machinery, and automobile parts such as cylinder heads, cylinder blocks, and gearboxes are all made of cast iron. It can withstand oxidation but is difficult to weld.

Wrought iron or malleable iron is the purest form of commercial iron and is prepared from cast iron by oxidising impurities in a reverberatory furnace lined with haematite. It is utilised to make pipes because of its high corrosion and fatigue resistance, as well as its superior welding and threading properties. Due to its good weldability and strong impact strength, it is used to make specific chains and crane hooks.

Steel is an alloy of iron and carbon. It contains approximately 1% of carbon. Steel is used because of its robust, hard, and corrosion-resistant properties. It is widely used in the construction of bridges, highways, airports, trains, skyscrapers, and other structures due to its low cost. It is also employed in the manufacture of major appliances, like washing machines, stoves, refrigerators, and dishwashers. as well as various construction materials, like steel beams, bars, pipes, etc.,

1. Titanium: Titanium is used as a whitening, brightening and opacifying agent in paints. It increases the whiteness and reflectivity. When you switch on the light in a room, the paint is highly reflective, making the space appear brighter since more light is reflected from the painted surfaces.

2. Gold: Gold is a precious metal. It has been used as currency for ages due to its high and consistent return value. Because of its high electrical conductivity, it is used in television sets, GPS devices, etc,. Because of its chemical inertness, it is used for cavities, caps and crowns.

3. Silver: It is used in making high capacity silver-cadmium and silver-zinc and batteries. Halides of silver like silver bromide are light-sensitive chemicals and are used in photographic paper and film.

4. Aluminium: Aluminium is used in local power distribution lines and overhead power transmission lines because of its high electrical conductivity. Because of its high resistance to corrosion, high strength, and light weight it is used in the manufacturing of aircraft.

5. Copper: It can be found in everything from cans, cooking foil, and saucepans to electricity wires, planes, and spacecraft. Because wire accounts for more than half of all copper use worldwide, electrical conductivity is very significant. Chemical vapour deposition is a semiconductor manufacturing process that involves depositing thin copper films from a gas-phase precursor. Copper is mostly employed as a gold and silver alloy, and it is frequently plated with one or the other.

7. Zinc: After iron, aluminium, and copper, zinc is the fourth most extensively used metal on the planet. It has excellent corrosion resistance properties. As a result, galvanising zinc, which is the process of adding thin coats of zinc to iron or steel to prevent corrosion, consumes around half of the zinc produced.

Practice Problems

Q1. Which out of following is not a carbonate ore?

Siderite
Calamine
Malachite
Bauxite

Solution:

Malachite →
Bauxite →
Calamine →
Siderite →

So, option B) is the correct answer.

Q2. The ore that contains metal in the form of fluoride is:

Magnetite
Dolomite
Malachite
Cryolite

Solution:

Magnetite →
Dolomite →
Malachite → ,
Cryolite →

So, option D) is the correct answer.

Q3. Which out of the following metals have sulphide ores as the common ores:

Solution:

Argentite (S) is an important ore of silver.
Galena () is an important ore of lead.
Copper has several sulphide ores including copper glance () and copper pyrites ().

So, option A) is the correct answer.

Q4. The ore that contains both iron and copper is:

Siderite
Calamite
Malachite
Copper pyrites

Solution: Copper pyrites is a copper iron sulphide mineral with the chemical formula . ore contains both copper and iron.

So, option D) is the correct answer.

Frequently Asked Questions - FAQ

Q1. Are all minerals ore?

Ans. The naturally occurring materials in which the metals or their compounds occur are called minerals. The minerals from which the metal can be extracted economically and conveniently are called ores.

Therefore, all ores are minerals, but not all minerals are ores.

Example: is abundantly present in Earth’s crust, but is not an ore as iron cannot be easily extracted from it.

Q2. Name some metals whose large deposits are found in India?

Ans. Mineral resources of essential metals such as iron, manganese, aluminium, magnesium, chromium, thorium, uranium, titanium, and lithium are found in India. They account for a fifth of all known mineral resources on the planet.

Q3. Where can we find bauxite ore in India?

Ans. Bauxite is an aluminium ore that is abundantly present in India. Bauxite production is projected to reach around 2 million tonnes per year. Bihar, Goa, Madhya Pradesh, Maharashtra, Tamil Nadu, Gujarat, Karnataka, Orissa, Uttar Pradesh, Andhra Pradesh, Jammu & Kashmir, and Rajasthan have significant bauxite deposits.

Q4. How are salts of silver used in photographic films?

Ans. Silver chloride readily decomposes into silver and chlorine when exposed to light. This is commonly utilised in the production of black-and-white photographic films. On the negative, the exposed region becomes black and the unexposed portion remains white. The rest is all darkroom techniques, which entails developing negative films and making positive prints from them.

Related Topics

Extraction of Crude Metal from Concentrated Ore	Extraction of Iron
Some Important Terms Used in Metallurgy	Concentration of Ores
Thermodynamical Principle of Metallurgy	Refining of Metals from Concentrated Ores