Gneiss

Amphibolite

Gneiss and Amphibolite

Gneiss

Amphibolite

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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

Amphibolite can be defined as a granular metamorphic rock which mainly consist of hornblende and plagioclase

1.2 History

1.2.1 Origin

Unknown

1.2.2 Discoverer

Unknown

Alexandre Brongniart

1.3 Etymology

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

From Amphibole + -ite

1.4 Class

Metamorphic Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Not Applicable

1.6 Other Categories

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Banded, Foliated, Platy

Banded, Foliated, Massive

2.2 Color

Black, Brown, Pink, Red, White

Black, Brown, Green, Grey

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

81% Metamorphic Rocks Rocks have it !

✔ ✘

81% Igneous Rocks Rocks have it !

2.4.2 Scratch Resistant

✔ ✘

65% Metamorphic Rocks Rocks have it !

✔ ✘

86% Igneous Rocks Rocks have it !

2.4.3 Stain Resistant

✔ ✘

42% Metamorphic Rocks Rocks have it !

✔ ✘

66% Igneous Rocks Rocks have it !

2.4.4 Wind Resistant

✔ ✘

19% Metamorphic Rocks Rocks have it !

✔ ✘

49% Igneous Rocks Rocks have it !

2.4.5 Acid Resistant

✔ ✘

15% Metamorphic Rocks Rocks have it !

✔ ✘

48% Igneous Rocks Rocks have it !

2.5 Appearance

Foliated

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Kitchens

3.1.2 Exterior Uses

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

As Building Stone, As Facing Stone, Paving Stone, Office Buildings

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone

As Dimension Stone, Building houses or walls, Cobblestones, Construction Aggregate, for Road Aggregate, Landscaping, Production of Glass and Ceramics, Roadstone

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Sculpture, Small Figurines

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Cemetery Markers, Commemorative Tablets, Creating Artwork

4 Types

4.1 Types

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

Hornblendite

4.2 Features

Generally rough to touch, Is one of the oldest rock

Clasts are smooth to touch, Matrix variable, Surfaces are often shiny

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

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Not Yet Used

Used

4.4 Fossils

Absent

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.

Amphibolite is a coarse-grained metamorphic rock which forms by metamorphism of mafic igneous rocks like basalt and gabbro or from the metamorphism of clay-rich sedimentary rocks like marl or graywacke.

5.2 Composition

5.2.1 Mineral Content

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

Amphibole, Andalusite, Biotite, Calcite, Epidote, Garnet, Hornblade, Kyanite, Magnetite, Olivine, Plagioclase, Pyroxene, Staurolite, Wollastonite

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

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

✔ ✘

50% Metamorphic Rocks Rocks have it !

✔ ✘

97% Igneous Rocks Rocks have it !

5.3.2 Types of Metamorphism

Impact Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

65% Metamorphic Rocks Rocks have it !

✔ ✘

99% Igneous Rocks Rocks have it !

5.3.4 Types of Weathering

Biological Weathering, Mechanical Weathering

Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

77% Metamorphic Rocks Rocks have it !

✔ ✘

92% Igneous Rocks Rocks have it !

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Chemical Erosion, Glacier Erosion, Sea Erosion, Wind Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6-7

6.1.2 Grain Size

Medium to Coarse Grained

6.1.3 Fracture

Irregular

Irregular to Conchoidal

6.1.4 Streak

White

White to Grey

6.1.5 Porosity

Very Less Porous

Less Porous

6.1.6 Luster

Dull

Vitreous to Dull

6.1.7 Compressive Strength

What Is Flint

⊕

▶

▼

125.00 N/mm²

Rank: 17 (Overall)▶

Not Available

Rank: N/A (Overall)▶

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What Is Obsidian

⊕

▶

175 (What Is Grani..)

◀ ▶ ADD ⊕

6.1.8 Cleavage

Poor

Irregular

6.1.9 Toughness

1.2

2.3

6.1.10 Specific Gravity

2.5-2.7

2.5

6.1.11 Transparency

Translucent to Opaque

Opaque

6.1.12 Density

2.6-2.9 g/cm³

2.85-3.07 g/cm³

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

What Is Banded ..

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▶

▼

Not Available

Rank: N/A (Overall)▶

Not Available

Rank: N/A (Overall)▶

▲

What Is Granulite

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▶

1.09 (What Is Trave..)

◀ ▶ ADD ⊕

6.2.2 Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat 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

Russia, Turkey

7.1.2 Africa

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

Burundi, Djibouti, Eritrea, Ethiopia, Kenya, Madagascar, Rwanda, Somalia, South Africa, Sudan, Tanzania, Uganda

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

Germany, Greece, Iceland, Norway, Poland

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

Canada, USA

7.2.2 South America

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

Brazil

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, New Zealand, Queensland, Victoria

South Australia, Western Australia

All about Gneiss and Amphibolite Properties

Know all about Gneiss and Amphibolite properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss and Amphibolite belong to Metamorphic Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Amphibolite is Banded, Foliated, Massive. Gneiss appears Foliated and Amphibolite appears Foliated. The luster of Gneiss is dull while that of Amphibolite is vitreous to dull. Gneiss is available in black, brown, pink, red, white colors whereas Amphibolite is available in black, brown, green, grey colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Amphibolite are cemetery markers, commemorative tablets, creating artwork.