Coal

Obsidian

Coal vs Obsidian

Coal

Obsidian

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1 Definition

1.1 Definition

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds

Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth

1.2 History

1.2.1 Origin

USA

Ethiopia

1.2.2 Discoverer

John Peter Salley

Obsius

1.3 Etymology

From the Old English term col, which has meant mineral of fossilized carbon since the 13th century

From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius

1.4 Class

Sedimentary Rocks

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Soft Rock

Durable Rock, Medium Hardness Rock

1.5 Family

1.5.1 Group

Not Applicable

Volcanic

1.6 Other Categories

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

Opaque Rock

2 Texture

2.1 Texture

Amorphous, Glassy

Glassy

2.2 Color

Black, Brown, Dark Brown, Grey, Light to Dark Grey

Black, Blue, Brown, Green, Orange, Red, Tan, Yellow

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

2.4.2 Scratch Resistant

✔ ✘

2.4.3 Stain Resistant

✔ ✘

2.4.4 Wind Resistant

✔ ✘

2.4.5 Acid Resistant

✔ ✘

2.5 Appearance

Veined or Pebbled

Shiny

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Not Yet Used

Decorative Aggregates, Interior Decoration

3.1.2 Exterior Uses

Not Yet Used

Garden Decoration

3.1.3 Other Architectural Uses

Not Yet Used

3.2 Industry

3.2.1 Construction Industry

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

Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points

3.2.2 Medical Industry

Not Yet Used

Surgery

3.3 Antiquity Uses

Artifacts

Artifacts, Jewellery

3.4 Other Uses

3.4.1 Commercial Uses

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

Creating Artwork, Mirror, Used in aquariums

4 Types

4.1 Types

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

Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian

4.2 Features

Helps in production of Heat and Electricity, Used as fossil fuel

Blocks negativity, Helps to protect against depression

4.3 Archaeological Significance

4.3.1 Monuments

Not Yet Used

4.3.2 Famous Monuments

Not Applicable

4.3.3 Sculpture

Not Yet Used

4.3.4 Famous Sculptures

Not Applicable

4.3.5 Pictographs

Not Used

Used

4.3.6 Petroglyphs

Not Used

Used

4.3.7 Figurines

Not Yet Used

4.4 Fossils

Present

Absent

5 Formation

5.1 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.

When the lava is released from volcano, it undergoes a very rapid cooling which freezes the mechanisms of crystallization. The result is a volcanic glass with a uniform smooth texture.

5.2 Composition

5.2.1 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

Not Available

5.2.2 Compound Content

Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur

Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Not Applicable

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Not Applicable

Chemical Erosion, Coastal Erosion, Glacier Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

1-1.55-5.5

1 7

6.1.2 Grain Size

Medium to Fine Coarse Grained

Not Applicable

6.1.3 Fracture

Conchoidal

6.1.4 Streak

Black

White

6.1.5 Porosity

Less Porous

Very Less Porous

6.1.6 Luster

Dull to Vitreous to Submetallic

Vitreous

6.1.7 Compressive Strength

NA0.15 N/mm²

0.15 450

6.1.8 Cleavage

Non-Existent

6.1.9 Toughness

Not Available

6.1.10 Specific Gravity

1.1-1.42.6-2.7

0 8.4

6.1.11 Transparency

Opaque

Translucent

6.1.12 Density

1100-1400 g/cm³2.6 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

1.32 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant

Heat Resistant, Impact Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

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

Afghanistan, Indonesia, Japan, Russia

7.1.2 Africa

Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania

Kenya

7.1.3 Europe

Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom

Greece, Hungary, Iceland, Italy, Turkey

7.1.4 Others

Not Yet Found

7.2 Deposits in Western Continents

7.2.1 North America

Canada, Mexico, USA

7.2.2 South America

Brazil, Chile, Colombia, Venezuela

Argentina, Chile, Ecuador, Peru

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, Queensland, Victoria

New Zealand

Coal vs Obsidian Information

Earth’s outer layer is covered by rocks and these rocks have different physical and chemical properties. As two rocks are not same, it’s fun to compare them. You can also know more about Coal and Obsidian Reserves. Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds. Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth. These rocks are composed of many distinct minerals. The process of formation of rocks is different for various rocks. Rocks are quarried from many years for various purposes. You can check out Coal vs Obsidian information and Coal vs Obsidian characteristics in the upcoming sections.

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Coal vs Obsidian Characteristics

Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Coal vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Coal and Properties of Obsidian. Learn more about Coal vs Obsidian in the next section. The interior uses of Coal include Not yet used whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Coal and Obsidian, they have various applications in construction industry. The uses of Coal in construction industry include Cement manufacture, For road aggregate, Making natural cement, Steel production and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.

More about Coal and Obsidian

Here you can know more about Coal and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Coal and Obsidian consists of mineral content and compound content. The mineral content of Coal includes 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 and mineral content of Obsidian is not available. You can also check out the list of all Sedimentary Rocks. When we have to compare Coal vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Coal is Veined or Pebbled and that of Obsidian is Shiny. Properties of rock is another aspect for Coal vs Obsidian. The hardness of Coal is 1-1.5 and that of Obsidian is 5-5.5. The types of Coal are Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite whereas types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Coal is black while that of Obsidian is white. The specific heat capacity of Coal is 1.32 kJ/Kg K and that of Obsidian is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Coal is heat resistant whereas Obsidian is heat resistant, impact resistant.