Tephrite

Pseudotachylite

Tephrite and Pseudotachylite

Tephrite

Pseudotachylite

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1 Definition

1.1 Definition

Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock

Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.

1.2 History

1.2.1 Origin

Germany

USA

1.2.2 Discoverer

Van Tooren

Unknown

1.3 Etymology

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

From pseudo- +‎ tachylite, a glassy rock generated by frictional heat within faults.

1.4 Class

Igneous Rocks

Metamorphic Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Volcanic

Not Applicable

1.6 Other Categories

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

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Aphanitic to Porphyritic

Quench

2.2 Color

Black, Brown, Colourless, Green, Grey, White

Black, Brown, Colourless, Green, Grey, Pink, 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

Vesicular

Dull and Soft

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Decorative Aggregates, Flooring, Homes, Interior Decoration

Decorative Aggregates, Entryways, Interior Decoration

3.1.2 Exterior Uses

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

As Building Stone, As Facing Stone, Garden Decoration

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

Landscaping

As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts, Sculpture

Artifacts, Monuments

3.4 Other Uses

3.4.1 Commercial Uses

Production of Lime, Soil Conditioner

Creating Artwork, Gemstone

4 Types

4.1 Types

Not Available

4.2 Features

Host Rock for Lead

4.3 Archaeological Significance

4.3.1 Monuments

Not Yet Used

Used

4.3.2 Famous Monuments

Not Applicable

Data Not Available

4.3.3 Sculpture

Used

Not Yet Used

4.3.4 Famous Sculptures

Data Not Available

Not Applicable

4.3.5 Pictographs

Not Used

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Used

Not Yet Used

4.4 Fossils

Absent

5 Formation

5.1 Formation

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.

Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.

5.2 Composition

5.2.1 Mineral Content

Alkali feldspar, Nepheline, Plagioclase, Pyroxene

Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides

5.2.2 Compound Content

CaO, Carbon Dioxide, MgO, Silicon Dioxide

Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Not Applicable

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

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

Not Applicable

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6.57

1 7

6.1.2 Grain Size

Medium to Fine Coarse Grained

Very fine-grained

6.1.3 Fracture

Uneven

6.1.4 Streak

Bluish Black

Light to dark brown

6.1.5 Porosity

Very Less Porous

Less Porous

6.1.6 Luster

Subvitreous to Dull

Vitreous

6.1.7 Compressive Strength

90.00 N/mm²60.00 N/mm²

0.15 450

6.1.8 Cleavage

Crenulation and Pervasive

Irregular

6.1.9 Toughness

2.4

Not Available

6.1.10 Specific Gravity

2.862.46-2.86

0 8.4

6.1.11 Transparency

Opaque

Transparent to Translucent

6.1.12 Density

2.8-2.9 g/cm³2.7-2.9 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

0.92 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant, Impact Resistant

Heat Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

Not Yet Found

South Korea

7.1.2 Africa

Namibia, Uganda

Western Africa

7.1.3 Europe

Germany, Hungary, Italy, Portugal, Spain

Great Britain, Switzerland

7.1.4 Others

Not Yet Found

7.2 Deposits in Western Continents

7.2.1 North America

USA

Not Yet Found

7.2.2 South America

Not Yet Found

7.3 Deposits in Oceania Continent

7.3.1 Australia

New Zealand, Western Australia

Central Australia, Western Australia

All about Tephrite and Pseudotachylite Properties

Know all about Tephrite and Pseudotachylite properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite belongs to Igneous Rocks while Pseudotachylite belongs to Metamorphic Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Pseudotachylite is Quench. Tephrite appears Vesicular and Pseudotachylite appears Dull and Soft. The luster of Tephrite is subvitreous to dull while that of Pseudotachylite is vitreous. Tephrite is available in black, brown, colourless, green, grey, white colors whereas Pseudotachylite is available in black, brown, colourless, green, grey, pink, white colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Pseudotachylite are creating artwork, gemstone.