Gneiss

Tephrite

Gneiss vs Tephrite

Gneiss

Tephrite

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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

Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock

1.2 History

1.2.1 Origin

Unknown

Germany

1.2.2 Discoverer

Unknown

Van Tooren

1.3 Etymology

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

From Greek tephra, ashes from Indo-European base, to burn

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

Volcanic

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

Aphanitic to Porphyritic

2.2 Color

Black, Brown, Pink, Red, White

Black, Brown, Colourless, Green, Grey, White

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

2.4.2 Scratch Resistant

✔ ✘

2.4.3 Stain Resistant

✔ ✘

2.4.4 Wind Resistant

✔ ✘

2.4.5 Acid Resistant

✔ ✘

2.5 Appearance

Foliated

Vesicular

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, 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, Garden Decoration, Office Buildings

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone

Landscaping

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Sculpture

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Production of Lime, Soil Conditioner

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

Host Rock for Lead

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.

Tephrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.

5.2 Composition

5.2.1 Mineral Content

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

Alkali feldspar, Nepheline, Plagioclase, Pyroxene

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, MgO, Silicon Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Impact Metamorphism

Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

76.5

1 7

6.1.2 Grain Size

Medium to Coarse Grained

Medium to Fine Coarse Grained

6.1.3 Fracture

Irregular

Uneven

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

125.00 N/mm²90.00 N/mm²

0.15 450

6.1.8 Cleavage

Poor

Crenulation and Pervasive

6.1.9 Toughness

1.2

2.4

6.1.10 Specific Gravity

2.5-2.72.86

0 8.4

6.1.11 Transparency

Translucent to Opaque

Opaque

6.1.12 Density

2.6-2.9 g/cm³2.8-2.9 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

NA0.92 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat Resistant, Impact 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

Namibia, 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, Hungary, Italy, Portugal, Spain

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

New Zealand, Western Australia

Gneiss vs Tephrite Information

Earth’s outer layer is covered by rocks and these rocks have different physical and chemical properties. As two rocks are not same, it’s fun to compare them. You can also know more about Gneiss and Tephrite Reserves. 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. Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock. These rocks are composed of many distinct minerals. The process of formation of rocks is different for various rocks. Rocks are quarried from many years for various purposes. You can check out Gneiss vs Tephrite information and Gneiss vs Tephrite characteristics in the upcoming sections.

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Gneiss vs Tephrite Characteristics

Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Gneiss vs Tephrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Gneiss and Properties of Tephrite. Learn more about Gneiss vs Tephrite in the next section. The interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Gneiss and Tephrite, they have various applications in construction industry. The uses of Gneiss in construction industry include As dimension stone and that of Tephrite include Landscaping.

More about Gneiss and Tephrite

Here you can know more about Gneiss and Tephrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Gneiss and Tephrite consists of mineral content and compound content. The mineral content of Gneiss includes Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon and mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene. You can also check out the list of all Metamorphic Rocks. When we have to compare Gneiss vs Tephrite, the texture, color and appearance plays an important role in determining the type of rock. Gneiss is available in black, brown, pink, red, white colors whereas, Tephrite is available in black, brown, colourless, green, grey, white colors. Appearance of Gneiss is Foliated and that of Tephrite is Vesicular. Properties of rock is another aspect for Gneiss vs Tephrite. The hardness of Gneiss is 7 and that of Tephrite is 6.5. The types of Gneiss are Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss. whereas types of Tephrite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Gneiss is white while that of Tephrite is bluish black. The specific heat capacity of Gneiss is Not Available and that of Tephrite is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant whereas Tephrite is heat resistant, impact resistant.