Schist

Tephrite

Schist and Tephrite

Schist

Tephrite

Add ⊕

1 Definition

1.1 Definition

Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation

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 French schiste, Greek skhistos i.e. split

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

1.4 Class

Metamorphic Rocks

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Medium Hardness Rock

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Not Applicable

Volcanic

1.6 Other Categories

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

2 Texture

2.1 Texture

Foliated, Platy

Aphanitic to Porphyritic

2.2 Color

Black, Blue, Brown, Dark Brown, Green, Grey, Silver

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

Layered and Shiny

Vesicular

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Decorative Aggregates, Floor Tiles, Interior Decoration

Decorative Aggregates, Flooring, Homes, Interior Decoration

3.1.2 Exterior Uses

Garden Decoration, Paving Stone

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

3.1.3 Other Architectural Uses

Not Yet Used

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone

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

Used in aquariums, Writing Slates

Production of Lime, Soil Conditioner

4 Types

4.1 Types

Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.

Not Available

4.2 Features

Easily splits into thin plates, Smooth to touch

Host Rock for Lead

4.3 Archaeological Significance

4.3.1 Monuments

Not Yet Used

4.3.2 Famous Monuments

Not Applicable

4.3.3 Sculpture

Not Yet Used

Used

4.3.4 Famous Sculptures

Not Applicable

Data Not Available

4.3.5 Pictographs

Used

Not Used

4.3.6 Petroglyphs

Used

Not Used

4.3.7 Figurines

Not Yet Used

Used

4.4 Fossils

Absent

5 Formation

5.1 Formation

Schist formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.

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

Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc

Alkali feldspar, Nepheline, Plagioclase, Pyroxene

5.2.2 Compound Content

CaO, Carbon Dioxide, MgO

CaO, Carbon Dioxide, MgO, Silicon Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Not Applicable

Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

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

6 Properties

6.1 Physical Properties

6.1.1 Hardness

3.5-46.5

1 7

6.1.2 Grain Size

Medium to Fine Coarse Grained

6.1.3 Fracture

Conchoidal

Uneven

6.1.4 Streak

White

Bluish Black

6.1.5 Porosity

Highly Porous

Very Less Porous

6.1.6 Luster

Shiny

Subvitreous to Dull

6.1.7 Compressive Strength

NA90.00 N/mm²

0.15 450

6.1.8 Cleavage

Slaty

Crenulation and Pervasive

6.1.9 Toughness

1.5

2.4

6.1.10 Specific Gravity

2.5-2.92.86

0 8.4

6.1.11 Transparency

Opaque

6.1.12 Density

2.8-2.9 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

Impact Resistant, Pressure Resistant, Water Resistant

Heat Resistant, Impact Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam

Not Yet Found

7.1.2 Africa

Egypt, Ethiopia, Morocco, Nigeria, South Africa

Namibia, Uganda

7.1.3 Europe

Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland

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

Brazil, Colombia, Guyana

Not Yet Found

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, New Zealand, Queensland

New Zealand, Western Australia

All about Schist and Tephrite Properties

Know all about Schist and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Schist belongs to Metamorphic Rocks while Tephrite belongs to Igneous Rocks.Texture of Schist is Foliated, Platy whereas that of Tephrite is Aphanitic to Porphyritic. Schist appears Layered and Shiny and Tephrite appears Vesicular. The luster of Schist is shiny while that of Tephrite is subvitreous to dull. Schist is available in black, blue, brown, dark brown, green, grey, silver colors whereas Tephrite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Schist are used in aquariums, writing slates and that of Tephrite are production of lime, soil conditioner.