Chert

Coquina

Chert and Coquina

Chert

Coquina

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1 Definition

1.1 Definition

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

Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates

1.2 History

1.2.1 Origin

Unknown

European Foreland Basins

1.2.2 Discoverer

Unknown

1.3 Etymology

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

From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)

1.4 Class

Sedimentary Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

Durable Rock, Soft Rock

1.5 Family

1.5.1 Group

Not Applicable

1.6 Other Categories

Fine Grained Rock, Opaque Rock

Coarse Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Banded, Rough

Clastic

2.2 Color

Black, Brown, Green, Grey, Red, White

Beige, Buff, Orange

2.3 Maintenance

Less

2.4 Durability

Durable

Non-Durable

2.4.1 Water Resistant

✔ ✘

59% Sedimentary Rocks Rocks have it !

✔ ✘

59% Sedimentary Rocks Rocks have it !

2.4.2 Scratch Resistant

✔ ✘

62% Sedimentary Rocks Rocks have it !

✔ ✘

62% Sedimentary Rocks Rocks have it !

2.4.3 Stain Resistant

✔ ✘

43% Sedimentary Rocks Rocks have it !

✔ ✘

43% Sedimentary Rocks Rocks have it !

2.4.4 Wind Resistant

✔ ✘

38% Sedimentary Rocks Rocks have it !

✔ ✘

38% Sedimentary Rocks Rocks have it !

2.4.5 Acid Resistant

✔ ✘

22% Sedimentary Rocks Rocks have it !

✔ ✘

22% Sedimentary Rocks Rocks have it !

2.5 Appearance

Glassy or Pearly

Layered, Banded, Veined and Shiny

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Decorative Aggregates, Homes

Decorative Aggregates, Homes, Hotels, Interior Decoration

3.1.2 Exterior Uses

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

Garden Decoration, Office Buildings

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

Arrowheads, Construction Aggregate, Cutting Tool, Spear Points

Building houses or walls, Construction Aggregate

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts, Monuments

Artifacts, Monuments, Sculpture, Small Figurines

3.4 Other Uses

3.4.1 Commercial Uses

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

Creating Artwork

4 Types

4.1 Types

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

Not Available

4.2 Features

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

Available in Lots of Colors and Patterns, Is one of the oldest rock

4.3 Archaeological Significance

4.3.1 Monuments

Used

4.3.2 Famous Monuments

Data Not Available

4.3.3 Sculpture

Not Yet Used

Used

4.3.4 Famous Sculptures

Not Applicable

Data Not Available

4.3.5 Pictographs

Not Used

Used

4.3.6 Petroglyphs

Not Used

Used

4.3.7 Figurines

Not Yet Used

Used

4.4 Fossils

Present

5 Formation

5.1 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.

Coquina is a sedimentary rock which is formed when billions of small clam-like seashell, called Coquina, or cockleshell are die and hence are deposited, buried and turns into a rock when pressure is applied.

5.2 Composition

5.2.1 Mineral Content

Quartz, Silicon

Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite

5.2.2 Compound Content

Silicon Dioxide

CaO, Carbon Dioxide, Iron(III) Oxide, MgO

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

19% Sedimentary Rocks Rocks have it !

✔ ✘

19% Sedimentary Rocks Rocks have it !

5.3.2 Types of Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

78% Sedimentary Rocks Rocks have it !

✔ ✘

78% Sedimentary Rocks Rocks have it !

5.3.4 Types of Weathering

Not Applicable

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

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86% Sedimentary Rocks Rocks have it !

✔ ✘

86% Sedimentary Rocks Rocks have it !

5.3.6 Types of Erosion

Chemical Erosion

Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6.5-7

1-2

6.1.2 Grain Size

Very fine-grained

Coarse Grained

6.1.3 Fracture

Uneven, Splintery or Conchoidal

Irregular

6.1.4 Streak

White

6.1.5 Porosity

Highly Porous

6.1.6 Luster

Waxy and Dull

Dull to Vitreous to Submetallic

6.1.7 Compressive Strength

What Is Flint

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▶

▼

450.00 N/mm²

Rank: 1 (Overall)▶

Not Available

Rank: N/A (Overall)▶

▲

What Is Obsidian

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▶

175 (What Is Grani..)

◀ ▶ ADD ⊕

6.1.8 Cleavage

Non-Existent

Not Available

6.1.9 Toughness

1.5

Not Available

6.1.10 Specific Gravity

2.5-2.8

1.10-2.24

6.1.11 Transparency

Translucent to Opaque

Opaque

6.1.12 Density

2.7 g/cm³

2.8-2.9 g/cm³

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

What Is Banded ..

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▶

▼

0.74 kJ/Kg K

Rank: 19 (Overall)▶

Not Available

Rank: N/A (Overall)▶

▲

What Is Granulite

⊕

▶

1.09 (What Is Trave..)

◀ ▶ ADD ⊕

6.2.2 Resistance

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

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

Not Yet Found

7.1.2 Africa

Kenya, Morocco, South Africa, Tanzania

Not Yet Found

7.1.3 Europe

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

United Kingdom

7.1.4 Others

Greenland, Mid-Atlantic Ridge

Not Yet Found

7.2 Deposits in Western Continents

7.2.1 North America

Canada, Mexico, USA

USA

7.2.2 South America

Bolivia, Brazil

Not Yet Found

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, Queensland, South Australia, Western Australia

Not Yet Found

All about Chert and Coquina Properties

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