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Coal
Coal

Porphyry
Porphyry



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Coal and Porphyry

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Definition

Definition

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix

History

Origin

USA
Egypt

Discoverer

John Peter Salley
Unknown

Etymology

From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites

Class

Sedimentary Rocks
Igneous Rocks

Sub-Class

Durable Rock, Soft Rock
Durable Rock, Hard Rock

Family

Group

-
Plutonic

Other Categories

Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock

Texture

Texture

Amorphous, Glassy
Porphyritic

Color

Black, Brown, Dark Brown, Grey, Light to Dark Grey
Black, Brown, Green, Grey, Red, Rust, White

Maintenance

Less
Less

Durability

Durable
Durable

Water Resistant

Scratch Resistant

Stain Resistant

Wind Resistant

Acid Resistant

Appearance

Veined or Pebbled
Dull

Uses

Architecture

Interior Uses

-
Decorative Aggregates, Interior Decoration

Exterior Uses

-
Garden Decoration, Paving Stone

Other Architectural Uses

-
Curbing

Industry

Construction Industry

Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
Construction Aggregate

Medical Industry

-
-

Antiquity Uses

Artifacts
Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
Creating Artwork, Gemstone, Jewelry

Types

Types

Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite
Rhomb Porphyry

Features

Helps in production of Heat and Electricity, Used as fossil fuel
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny

Archaeological Significance

Monuments

-
-

Famous Monuments

-
-

Sculpture

-
-

Famous Sculptures

-
-

Pictographs

-
-

Petroglyphs

-
-

Figurines

-
-

Fossils

Present
Absent

Formation

Formation

Coal forms from the accumulation of plant debris in a swamp environment which is buried by sediments such as mud or sand and then compacted to form coal.
Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.

Composition

Mineral Content

Analcime, Apatite, Barite, Calcite, Chalcopyrite, Chlorite, Chromite, Clausthalite, Clay Minerals, Crandallite Group, Dolomite, Feldspar, Galena, Gypsum, Marcasite, Muscovite or Illite, Pyrite, Quartz, Siderite, Sphalerite, Zircon
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica

Compound Content

Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide

Transformation

Metamorphism

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism

Weathering

Types of Weathering

-
Biological Weathering, Chemical Weathering

Erosion

Types of Erosion

-
Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

1-1.56-7
1 7
👆🏻

Grain Size

Medium to Fine Coarse Grained
Fine Grained

Fracture

Conchoidal
Irregular

Streak

Black
White

Porosity

Less Porous
Less Porous

Luster

Dull to Vitreous to Submetallic
Dull

Compressive Strength

-150.00 N/mm2
0.15 450
👆🏻

Cleavage

-
-

Toughness

-
1.7

Specific Gravity

1.1-1.42.5-4
0 8.4
👆🏻

Transparency

Opaque
Translucent to Opaque

Density

1100-1400 g/cm32.5-2.52 g/cm3
0 1400
👆🏻

Thermal Properties

Specific Heat Capacity

1.32 kJ/Kg K0.71 kJ/Kg K
0.14 3.2
👆🏻

Resistance

Heat Resistant
Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam

Africa

Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Egypt, Ethiopia, Ghana, South Africa

Europe

Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland

Others

-
Greenland

Deposits in Western Continents

North America

Canada, Mexico, USA
Canada, Cuba, Jamaica, USA

South America

Brazil, Chile, Colombia, Venezuela
Bolivia, Brazil, Colombia, Ecuador, Paraguay

Deposits in Oceania Continent

Australia

New South Wales, Queensland, Victoria
New South Wales, New Zealand, Western Australia

All about Coal and Porphyry Properties

Know all about Coal and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Coal belongs to Sedimentary Rocks while Porphyry belongs to Igneous Rocks.Texture of Coal is Amorphous, Glassy whereas that of Porphyry is Porphyritic. Coal appears Veined or Pebbled and Porphyry appears Dull. The luster of Coal is dull to vitreous to submetallic while that of Porphyry is dull. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Porphyry is available in black, brown, green, grey, red, rust, white colors. The commercial uses of Coal are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry and that of Porphyry are creating artwork, gemstone, jewelry.