Gneiss

Coquina

Gneiss and Coquina

Gneiss

Coquina

Add ⊕

1 Definition

1.1 Definition

Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks

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 the Middle High German verb gneist (to spark; so called because the rock glitters)

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

1.4 Class

Metamorphic Rocks

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

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

Coarse Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Banded, Foliated, Platy

Clastic

2.2 Color

Black, Brown, Pink, Red, White

Beige, Buff, Orange

2.3 Maintenance

2.4 Durability

Durable

Non-Durable

2.4.1 Water Resistant

✔ ✘

81% Metamorphic Rocks Rocks have it !

✔ ✘

59% Sedimentary Rocks Rocks have it !

2.4.2 Scratch Resistant

✔ ✘

65% Metamorphic Rocks Rocks have it !

✔ ✘

62% Sedimentary Rocks Rocks have it !

2.4.3 Stain Resistant

✔ ✘

42% Metamorphic Rocks Rocks have it !

✔ ✘

43% Sedimentary Rocks Rocks have it !

2.4.4 Wind Resistant

✔ ✘

19% Metamorphic Rocks Rocks have it !

✔ ✘

38% Sedimentary Rocks Rocks have it !

2.4.5 Acid Resistant

✔ ✘

15% Metamorphic Rocks Rocks have it !

✔ ✘

22% Sedimentary Rocks Rocks have it !

2.5 Appearance

Foliated

Layered, Banded, Veined and Shiny

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, Homes, Hotels, Interior Decoration

3.1.2 Exterior Uses

As Building Stone, As Facing Stone, Garden Decoration, Paving Stone

Garden Decoration, Office Buildings

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone

Building houses or walls, Construction Aggregate

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Monuments, Sculpture, Small Figurines

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Creating Artwork

4 Types

4.1 Types

Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.

Not Available

4.2 Features

Generally rough to touch, Is one of the oldest rock

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

Konark Sun Temple in India, Washington Monument, US

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

Absent

Present

5 Formation

5.1 Formation

Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.

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

Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon

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

5.2.2 Compound Content

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

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

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

50% Metamorphic Rocks Rocks have it !

✔ ✘

19% Sedimentary Rocks Rocks have it !

5.3.2 Types of Metamorphism

Impact Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

65% Metamorphic Rocks Rocks have it !

✔ ✘

78% Sedimentary Rocks Rocks have it !

5.3.4 Types of Weathering

Biological Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

77% Metamorphic Rocks Rocks have it !

✔ ✘

86% Sedimentary Rocks Rocks have it !

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

1-2

6.1.2 Grain Size

Medium to Coarse Grained

Coarse Grained

6.1.3 Fracture

Irregular

6.1.4 Streak

White

6.1.5 Porosity

Very Less Porous

Highly Porous

6.1.6 Luster

Dull

Dull to Vitreous to Submetallic

6.1.7 Compressive Strength

What Is Flint

⊕

▶

▼

125.00 N/mm²

Rank: 17 (Overall)▶

Not Available

Rank: N/A (Overall)▶

▲

What Is Obsidian

⊕

▶

175 (What Is Grani..)

◀ ▶ ADD ⊕

6.1.8 Cleavage

Poor

Not Available

6.1.9 Toughness

1.2

Not Available

6.1.10 Specific Gravity

2.5-2.7

1.10-2.24

6.1.11 Transparency

Translucent to Opaque

Opaque

6.1.12 Density

2.6-2.9 g/cm³

2.8-2.9 g/cm³

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

What Is Banded ..

⊕

▶

▼

Not Available

Rank: N/A (Overall)▶

Not Available

Rank: N/A (Overall)▶

▲

What Is Granulite

⊕

▶

1.09 (What Is Trave..)

◀ ▶ ADD ⊕

6.2.2 Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia

Not Yet Found

7.1.2 Africa

Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo

Not Yet Found

7.1.3 Europe

Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom

United Kingdom

7.1.4 Others

Not Yet Found

7.2 Deposits in Western Continents

7.2.1 North America

Canada, Costa Rica, Cuba, Mexico, Panama, USA

USA

7.2.2 South America

Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela

Not Yet Found

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, New Zealand, Queensland, Victoria

Not Yet Found

All about Gneiss and Coquina Properties

Know all about Gneiss and Coquina properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Coquina belongs to Sedimentary Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Coquina is Clastic. Gneiss appears Foliated and Coquina appears Layered, Banded, Veined and Shiny. The luster of Gneiss is dull while that of Coquina is dull to vitreous to submetallic. Gneiss is available in black, brown, pink, red, white colors whereas Coquina is available in beige, buff, orange colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Coquina are creating artwork.