Adakite and Gossan

Adakite

Gossan

Definition

Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs

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

History

Origin

Adak, Aleutian Islands

Indonesia

Discoverer

Defant and Drummond

Cornish Gossen

Etymology

From Adak, Aleutian Islands

From Cornish gossen from gos, blood from Old Cornish guit

Class

Igneous Rocks

Metamorphic Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Not Applicable

Other Categories

Fine Grained Rock, Medium Grained Rock, Opaque Rock

Texture

Porphyritic

Rough, Sandy

Color

Black, Brown, Light to Dark Grey

Brown, Brown- Black, Gold, Green, Rust

Maintenance

Less

Durability

Durable

Water Resistant

Yes

Scratch Resistant

Yes

Stain Resistant

Yes

Wind Resistant

Yes

Acid Resistant

Yes

Appearance

Dull and Soft

Dull and Banded

Uses

Architecture

Interior Uses

Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens

Countertops, Decorative Aggregates, Interior Decoration

Exterior Uses

As Building Stone, As Facing Stone, Office Buildings

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

Other Architectural Uses

Whetstones

Curbing

Industry

Construction Industry

As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone

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

Medical Industry

Not Yet Used

Antiquity Uses

Monuments, Sculpture, Small Figurines

Artifacts

Other Uses

Commercial Uses

Commemorative Tablets, Pottery, Used in aquariums

Cemetery Markers, Commemorative Tablets, Gemstone

Types

Not Available

Translocated gossan and Leakage gossan

Features

Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock

Clasts are smooth to touch, Easily splits into thin plates

Archaeological Significance

Monuments

Used

Not Yet Used

Famous Monuments

Data Not Available

Not Applicable

Sculpture

Used

Not Yet Used

Famous Sculptures

Data Not Available

Not Applicable

Pictographs

Used

Petroglyphs

Used

Figurines

Used

Not Yet Used

Fossils

Absent

Formation

Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.

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

Composition

Mineral Content

Olivine, Plagioclase, Pyroxene

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

Compound Content

Aluminium Oxide, MgO, Silicon Dioxide

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

Transformation

Metamorphism

Yes

Types of Metamorphism

Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

Not Applicable

Weathering

Yes

Types of Weathering

Chemical Weathering, Mechanical Weathering

Not Applicable

Erosion

Yes

Types of Erosion

Coastal Erosion, Sea Erosion, Water Erosion

Chemical Erosion, Sea Erosion, Wind Erosion

Properties

Physical Properties

Hardness

3-4

4-5

Grain Size

Fine to Medium Grained

Fracture

Conchoidal

Streak

Bluish Black

White to Grey

Porosity

Less Porous

Highly Porous

Luster

Grainy, Pearly and Vitreous

Metallic

Cleavage

Not Available

Toughness

Not Available

Specific Gravity

Not Available

2.0

Transparency

Opaque

Density

Not Available

Thermal Properties

Specific Heat Capacity

Not Available

0.24 kJ/Kg K

Resistance

Heat Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Impact Resistant, Pressure Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Russia

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

Africa

Ethiopia, Somalia, South Africa

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

Europe

Iceland

Albania, France, Germany, Great Britain, United Kingdom

Others

Not Yet Found

Deposits in Western Continents

North America

Canada, USA

South America

Brazil

Brazil, Colombia, Ecuador

Deposits in Oceania Continent

Australia

Not Yet Found

New South Wales, South Australia, Western Australia

Summary >>

<< Reserves

All about Adakite and Gossan Properties

Know all about Adakite and Gossan properties here. All properties of rocks are important as they define the type of rock and its application. Adakite belongs to Igneous Rocks while Gossan belongs to Metamorphic Rocks.Texture of Adakite is Porphyritic whereas that of Gossan is Rough, Sandy. Adakite appears Dull and Soft and Gossan appears Dull and Banded. The luster of Adakite is grainy, pearly and vitreous while that of Gossan is metallic. Adakite is available in black, brown, light to dark grey colors whereas Gossan is available in brown, brown- black, gold, green, rust colors. The commercial uses of Adakite are commemorative tablets, pottery, used in aquariums and that of Gossan are cemetery markers, commemorative tablets, gemstone.