Gossan

Tephrite

Gossan and Tephrite

Gossan

Tephrite

Add ⊕

1 Definition

1.1 Definition

Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.

Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock

1.2 History

1.2.1 Origin

Indonesia

Germany

1.2.2 Discoverer

Cornish Gossen

Van Tooren

1.3 Etymology

From Cornish gossen from gos, blood from Old Cornish guit

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

Fine Grained Rock, Medium Grained Rock, Opaque Rock

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

2 Texture

2.1 Texture

Rough, Sandy

Aphanitic to Porphyritic

2.2 Color

Brown, Brown- Black, Gold, Green, Rust

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

Dull and Banded

Vesicular

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Interior Decoration

Decorative Aggregates, Flooring, Homes, Interior Decoration

3.1.2 Exterior Uses

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

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, Cement Manufacture, Construction Aggregate, for Road Aggregate

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, Commemorative Tablets, Gemstone

Production of Lime, Soil Conditioner

4 Types

4.1 Types

Translocated gossan and Leakage gossan

Not Available

4.2 Features

Clasts are smooth to touch, Easily splits into thin plates

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

Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.

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

Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon

Alkali feldspar, Nepheline, Plagioclase, Pyroxene

5.2.2 Compound Content

Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur

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

Not Applicable

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Sea Erosion, Wind Erosion

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

6 Properties

6.1 Physical Properties

6.1.1 Hardness

4-56.5

1 7

6.1.2 Grain Size

Fine to Medium Grained

Medium to Fine Coarse Grained

6.1.3 Fracture

Conchoidal

Uneven

6.1.4 Streak

White to Grey

Bluish Black

6.1.5 Porosity

Highly Porous

Very Less Porous

6.1.6 Luster

Metallic

Subvitreous to Dull

6.1.7 Compressive Strength

NA90.00 N/mm²

0.15 450

6.1.8 Cleavage

Not Available

Crenulation and Pervasive

6.1.9 Toughness

Not Available

2.4

6.1.10 Specific Gravity

2.02.86

0 8.4

6.1.11 Transparency

Opaque

6.1.12 Density

Not Available2.8-2.9 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

0.24 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant, Impact Resistant, Pressure Resistant

Heat Resistant, Impact Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

China, India, Indonesia, Russia, Singapore, South Korea

Not Yet Found

7.1.2 Africa

Cape Verde, Ethiopia, Ghana, South Africa, Western Africa

Namibia, Uganda

7.1.3 Europe

Albania, France, Germany, Great Britain, 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, USA

USA

7.2.2 South America

Brazil, Colombia, Ecuador

Not Yet Found

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, South Australia, Western Australia

New Zealand, Western Australia

All about Gossan and Tephrite Properties

Know all about Gossan and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Gossan belongs to Metamorphic Rocks while Tephrite belongs to Igneous Rocks.Texture of Gossan is Rough, Sandy whereas that of Tephrite is Aphanitic to Porphyritic. Gossan appears Dull and Banded and Tephrite appears Vesicular. The luster of Gossan is metallic while that of Tephrite is subvitreous to dull. Gossan is available in brown, brown- black, gold, green, rust colors whereas Tephrite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Gossan are cemetery markers, commemorative tablets, gemstone and that of Tephrite are production of lime, soil conditioner.