Chert

Lignite

Chert and Lignite

Chert

Lignite

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Definition

Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture

Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat

History

Origin

France

Discoverer

Unknown

Etymology

From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use

From French, Latin lignum wood + -ite1

Class

Sedimentary Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Soft Rock

Family

Group

Other Categories

Fine Grained Rock, Opaque Rock

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

Texture

Banded, Rough

Amorphous, Glassy

Color

Black, Brown, Green, Grey, Red, White

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

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Glassy or Pearly

Veined or Pebbled

Uses

Architecture

Interior Uses

Decorative Aggregates, Homes

Exterior Uses

As Building Stone, As Facing Stone, Garden Decoration, Office Buildings

Other Architectural Uses

Curbing

Industry

Construction Industry

Arrowheads, Construction Aggregate, Cutting Tool, Spear Points

for Road Aggregate, Steel Production

Medical Industry

Antiquity Uses

Artifacts, Monuments

Other Uses

Commercial Uses

Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms

Electricity Generation

Types

Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter

Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite

Features

Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate

Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Present

Formation

Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.

Coal formation takes place due to accumulation of plant debris in a swamp environment. The Coal formation process continues, as peat turns into lignite brown or black coal at increasing heat and pressure.

Composition

Mineral Content

Quartz, Silicon

Compound Content

Silicon Dioxide

Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion

Chemical Erosion, Water Erosion, Wind Erosion

Properties

Physical Properties

Hardness

6.5-71

1 7

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Grain Size

Very fine-grained

Medium to Fine Coarse Grained

Fracture

Uneven, Splintery or Conchoidal

Conchoidal

Streak

White

Black

Porosity

Highly Porous

Luster

Waxy and Dull

Dull to Vitreous to Submetallic

Compressive Strength

450.00 N/mm²-

0.15 450

👆🏻

Cleavage

Toughness

1.5

Specific Gravity

2.5-2.81.1-1.4

0 8.4

👆🏻

Transparency

Translucent to Opaque

Opaque

Density

2.7 g/cm³800-801 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.74 kJ/Kg K1.26 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Heat Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam

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

Africa

Kenya, Morocco, South Africa, Tanzania

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

Europe

Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom

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

Others

Greenland, Mid-Atlantic Ridge

Deposits in Western Continents

North America

Canada, Mexico, USA

South America

Bolivia, Brazil

Brazil, Chile, Colombia, Venezuela

Deposits in Oceania Continent

Australia

New South Wales, Queensland, South Australia, Western Australia

New South Wales, Queensland, Victoria

All about Chert and Lignite Properties

Know all about Chert and Lignite properties here. All properties of rocks are important as they define the type of rock and its application. Chert and Lignite belong to Sedimentary Rocks.Texture of Chert is Banded, Rough whereas that of Lignite is Amorphous, Glassy. Chert appears Glassy or Pearly and Lignite appears Veined or Pebbled. The luster of Chert is waxy and dull while that of Lignite is dull to vitreous to submetallic. Chert is available in black, brown, green, grey, red, white colors whereas Lignite is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms and that of Lignite are electricity generation.