3- Minerals.pdf

Minerals

Dr. Naveed Ahmad

Presentation Contents

Basic Definition

What is a Mineral?

Minerals Occurrence

Minerals Characteristics

Rocks, Ores, Gems

Minerals Chemistry

The Chemistry of Minerals

Main Drivers

Physical Properties ofMinerals

Major Physical Properties

Colour and Streak

Cleavage, Parting, Fractureand Tenacity

Mohos Hardness Scale

Lustre and Diaphaneity

Crystal Structure and Habit

Specific Gravity

Miscellaneous

Minerals Classes

Mineral Classification

Major Classes

Minerals Resources ofPakistan

Q & A

MineralsCE 312 Engineering Geology and Seismology

Dr. Naveed Ahmad

Professor (Asst.), Tenure Track

Earthquake Engineering CenterUET Peshawar, KP

PAKISTANE-Mail: [email protected]

September 22, 2014

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

What is a Mineral?

CE-312 Engineering Geology and Seismology Course Instructor Dr. Naveed Ahmad, EEC, UET Peshawar

A mineral is a naturally occurring substance, Solid and stable at room temperature, Representable by a chemical formula, Usually abiogenic, and Has an ordered atomic structure.

A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes (IMA, 1995).

It is different from a rock, It is an aggregate of minerals or non-minerals, and It does not have a specific chemical composition.

The exact definition of a mineral is under debate, Especially with respect to the requirement of a valid species be

abiogenic, and To a lesser extent with regards to it having an ordered atomic structure.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Minerals Occurrence


There are about 4,900 known mineral species; Over 4,660 of these have been approved by the International

Mineralogical Association. The silicate minerals compose over 90% of the Earths crust.

The diversity and abundance of mineral species is controlled by the Earths chemistry. Silicon and oxygen constitute approximately 75% of the Earths

crust.

Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure

distinguish various species, and These properties in turn are influenced by the minerals

geological environment of formation.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A



Changes in the temperature, pressure, and bulk composition of a rock mass cause changes in its mineralogy;

A rock can maintain its bulk composition, But as long as temperature and pressure change, its

mineralogy can change as well.

Minerals can be described by various physical properties, Which relate to their chemical structure and composition.

Common distinguishing characteristics include Crystal structure and habit, hardness, lustre, diaphaneity,

colour, streak, tenacity, cleavage, fracture, parting, and specific gravity.

More specific tests for minerals include reaction to acid, magnetism, taste or smell, and radioactivity.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Rocks, Ores, Gems


A rock is either an aggregate of one or more minerals, or not composed of minerals at all.

In rocks, some mineral species and groups are much more abundant than others; These are termed the rock-forming minerals.

Overall, around 150 minerals are considered particularly important.

Most of the Minerals are silicates, Feldspars, Micas, Amphiboles, Pyroxenes, Olivines, and Calcite

Ores are minerals that have a high concentration of a certain element, typically a metal.

Gems are minerals with an ornamental value, and are distinguished from non-gems by their beauty, durability, and usually, rarity.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A



The abundance and diversity of minerals is controlled directly by their chemistry, In turn dependent on elemental abundances in the Earth.

The majority of minerals observed are derived from the Earths crust.

Eight elements account for most of the key components of minerals, due to their abundance in the crust. Oxygen, silicon, aluminium, iron, magnesium, calcium, sodium and

potassium. These eight elements, summing to over 98% of the crust by weight. Oxygen composes 46.6% of the crust by weight, and silicon accounts

for 27.7%.

The minerals that form are directly controlled by the bulk chemistry of the parent body. For example, a magma rich in iron and magnesium will form mafic

minerals, such as olivine and the pyroxenes.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Main Drivers


Changes in temperature and pressure, and composition alter the mineralogy of a rock sample. Changes in composition can be caused by processes such as

weathering or metasomatism (hydrothermal alteration).

Changes in temperature and pressure occur when the host rock undergoes tectonic or magmatic movement into differing physical regimes.

Changes in thermodynamic conditions make it favourable for mineral assemblages to react with each other to produce new minerals; It is possible for two rocks to have an identical or a very similar

bulk rock chemistry without having a similar mineralogy.

This process of mineralogical alteration is related to the rock cycle.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Major Physcial Properties


A mineral can be identified by several physical properties.

Some of the minerals can only be classified by more complex optical, chemical or X-ray diffraction analysis.

Physical properties applied for classification include, Crystal structure and habit, Hardness, Lustre, Diaphaneity, Colour, Streak, Cleavage and fracture, and Specific gravity.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Colour and Streak


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Colour and Streak - Pseudochromatic


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Cleavage, Parting, Fracture and Tenacity


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A



Mohs Scale of Hardness Devised by an Austrian

mineralogist Friedrich Mohs in 1822.

A ability of a mineral to scratch another. Place ten minerals in order:

from soft (1) to hard (10) A mineral can scratch

minerals with low number but not minerals with high number.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A



Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Specific Gravity


Specific gravity refers to the density of a mineral i.e. mass per unit volume.

The specific gravity of a mineral can be measured in a laboratory, provided the crystal is not too small.

The specific gravity is given by the relation,

where W1 is the weight of the mineral grain in air, and W2 is the weight in water.

The specific gravity of a mineral is estimated as

=W1

W1 W2

Low 2.2 4.0, included silicates, carbonates, sulphates and halides Medium 4.5 7.5, include metallic ores such as sulphides and oxides High > 8.0, include native metallic elements such as pure copper, gold and

silver

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Miscellaneous


Transperancy How clearly an object can be seen through a crystal. Transparent, Subtransparent, Translucent, Subtranslucent, Opaque

Reaction with Acid A drop of cold 10% dilute HCl put on certain minerals causes reaction. In calcite CaCO3, bubbles of carbon dioxide make the acid froth (foam),

and In some sulphide ores, hydrogen sulphide is produced.

Tenacity How the mineral deforms when it is crushed or bent. Brittle, Flexible, Elastic, Malleable, Sectile, Ductile.

Magnetism Its a very conspicuous property of minerals. Magnetite exhibits this property strongly.

Taste Halite, NaCl, is table salt; its potassium-bearing counterpart, sylvite, has a pronounced bitter taste.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A



Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Tectosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Phyllosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Inosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Cyclosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Sorosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Orthosilicates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Native Elements


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Sulfides


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Oxides


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Halite


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Carbonates


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Sulfate


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Phosphate


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Spatial Trend


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Overview


Pakistan is endowed with significant mineral resources and emerging as a very promising area for exploration of mineral deposits.

Based on available information, countrys more than 600,000 sq-kms of outcrop area demonstrates varied geological potential for metallic/non-metallic mineral deposits.

Exploration by government agencies as well as by multinational mining companies and various regional geological surveys, conducted have confirmed potential for metallic minerals, Copper, gold, silver, platinum, chromites, iron, lead and zinc. Industrial minerals: multi-coloured granite, marble and other

dimensional stones of high quality.

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Overview


The major production is of coal, rock salt, and other industrial and construction minerals.

The value addition is mainly concentrated in five principal minerals, Limestone, coal, gypsum, sulphur, crude oil, and natural

gas

The current contribution of mineral sector to the GDP is about 0.50%

It is likely to increase considerably on the development and commercial exploitation for, Saindak and Reco Diq copper deposits, Duddar Zinc lead,

Thar coal and Gemstone deposits

Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Major Minerals


Minerals

Dr. Naveed Ahmad


Basic Definition

What is a Mineral?

Minerals Occurrence


Rocks, Ores, Gems

Minerals Chemistry


Main Drivers



Colour and Streak





Specific Gravity

Miscellaneous

Minerals Classes


Major Classes


Q & A

Q & A


Many Thanks for Your Attention

Questions & Answers

See You in The Next Class

Basic DefinitionWhat is a Mineral?Minerals OccurrenceMinerals CharacteristicsRocks, Ores, Gems

Minerals ChemistryThe Chemistry of MineralsMain Drivers

Physical Properties of MineralsMajor Physical PropertiesColour and StreakCleavage, Parting, Fracture and TenacityMoho's Hardness ScaleLustre and DiaphaneityCrystal Structure and HabitSpecific GravityMiscellaneous

Minerals ClassesMineral ClassificationMajor Classes

Minerals Resources of PakistanQ & A

Documents

3- Minerals.pdf