Gneiss

Trondhjemite

Gneiss and Trondhjemite

Gneiss

Trondhjemite

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

Trondhjemite is a leucocratic (light-colored) intrusive igneous rock. It is a variety of tonalite in which the plagioclase is mostly in the form of oligoclase. Trondhjemites are sometimes known as plagiogranites.

1.2 History

1.2.1 Origin

Unknown

Tonale, Italy

1.2.2 Discoverer

Unknown

1.3 Etymology

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

Not Available

1.4 Class

Metamorphic Rocks

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Not Applicable

Plutonic

1.6 Other Categories

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

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

2 Texture

2.1 Texture

Banded, Foliated, Platy

Phaneritic

2.2 Color

Black, Brown, Pink, Red, White

Black, Brown, Light to Dark Grey, White

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

Banded and Foilated

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration

3.1.2 Exterior Uses

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

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

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone

As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road 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

Cemetery Markers, 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

Is one of the oldest rock, Typically speckled black and white.

4.3 Archaeological Significance

4.3.1 Monuments

Used

Not Yet Used

4.3.2 Famous Monuments

Konark Sun Temple in India, Washington Monument, US

Not Applicable

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.

When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes trondhjemite with quartz as major mineral.

5.2 Composition

5.2.1 Mineral Content

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

Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon

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

NaCl, CaO, MgO, Silicon 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

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

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

Biological 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, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6-7

6.1.2 Grain Size

Medium to Coarse Grained

Medium to Fine Coarse Grained

6.1.3 Fracture

Irregular

Conchoidal

6.1.4 Streak

White

Bluish Black

6.1.5 Porosity

Very Less Porous

6.1.6 Luster

Dull

Subvitreous to Dull

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

2.1

6.1.10 Specific Gravity

2.5-2.7

2.86-3

6.1.11 Transparency

Translucent to Opaque

Opaque

6.1.12 Density

2.6-2.9 g/cm³

2.73 g/cm³

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

What Is Banded ..

⊕

▶

▼

Not Available

Rank: N/A (Overall)▶

0.92 kJ/Kg K

Rank: 10 (Overall)▶

▲

What Is Granulite

⊕

▶

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

Not Yet Found

7.1.2 Africa

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

Egypt

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

Finland, Germany, Italy, Romania, Sweden, Turkey

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

Argentina, Bolivia, Chile, Colombia, Ecuador, Peru

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, New Zealand, Queensland, Victoria

New Zealand, South Australia, Western Australia

All about Gneiss and Trondhjemite Properties

Know all about Gneiss and Trondhjemite properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Trondhjemite belongs to Igneous Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Trondhjemite is Phaneritic. Gneiss appears Foliated and Trondhjemite appears Banded and Foilated. The luster of Gneiss is dull while that of Trondhjemite is subvitreous to dull. Gneiss is available in black, brown, pink, red, white colors whereas Trondhjemite is available in black, brown, light to dark grey, white colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Trondhjemite are cemetery markers, creating artwork.