Gneiss

Granite

Gneiss and Granite

Gneiss

Granite

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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

Granite is a very hard, granular, crystalline igneous rock which consists mainly of quartz, mica, and feldspar and is often used as building stone

History

Origin

Discoverer

Unknown

Alexander von Humboldt

Etymology

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

From Italian granito, which means grained rock, from grano grain, and from Latin granum

Class

Metamorphic Rocks

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Plutonic

Other Categories

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

Coarse Grained Rock, Opaque Rock

Texture

Banded, Foliated, Platy

Granular, Phaneritic

Color

Black, Brown, Pink, Red, White

Black, Grey, Orange, Pink, White

Maintenance

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Foliated

Veined or Pebbled

Uses

Architecture

Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads

Exterior Uses

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

As Building Stone, As Facing Stone, Bridges, Paving Stone, Garden Decoration, Near Swimming Pools, Office Buildings, Resorts

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone

Medical Industry

Antiquity Uses

Artifacts

Monuments, Sculpture, Small Figurines

Other Uses

Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Curling, Gemstone, Laboratory bench tops, Tombstones, Used in aquariums

Types

Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.

Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite, Hybrid Granite, Granodiorite and Alkali Feldspar Granite

Features

Generally rough to touch, Is one of the oldest rock

Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock

Archaeological Significance

Monuments

Famous Monuments

Konark Sun Temple in India, Washington Monument, US

Agia Sophia in Istanbul, Turkey, Blue Domed Church in Santorini, Greece, Blue Mosque in Istanbul, Charminar in Hyderabad, India, Diana, Princess of Wales Memorial Fountain in London, UK, Ephesus in Turkey, Georgia Guidestones in Georgia, US, Hermitage in Saint Petersburg, Khajuraho Temples, India, Mahabalipuram in Tamil Nadu, India, Mysore Palace in Karnataka, India, Signers Monument in Augusta, Georgia, Statue of Liberty in New York, USA, Taj Mahal in Agra, India, Tower Bridge in London, Vietnam Veterans Memorial in Washington, US, Washington Monument, US

Sculpture

Famous Sculptures

Avukana Buddha Statue in Sri Lanka, Lincoln Memorial in America, Mount Rushmore National Memorial in South Dakota, US, The Colossal Red Granite Statue of Amenhotep III in Karnak, Egypt

Pictographs

Petroglyphs

Figurines

Fossils

Absent

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.

Granite is an intrusive igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks

Composition

Mineral Content

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

Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz

Compound Content

Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide

Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Impact Metamorphism

Burial Metamorphism, Cataclastic Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Mechanical Weathering

Biological Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Chemical Erosion, Sea Erosion, Water Erosion

Properties

Physical Properties

Hardness

76-7

1 7

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Grain Size

Medium to Coarse Grained

Large and Coarse Grained

Fracture

Irregular

Streak

White

Porosity

Very Less Porous

Less Porous

Luster

Dull

Dull to Grainy with Sporadic parts Pearly and Vitreous

Compressive Strength

125.00 N/mm²175.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

1.2

Specific Gravity

2.5-2.72.6-2.7

0 8.4

👆🏻

Transparency

Translucent to Opaque

Opaque

Density

2.6-2.9 g/cm³2.65-2.75 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.70 kJ/Kg K0.79 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia

China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam

Africa

Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo

Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa

Europe

Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom

Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic

Others

Deposits in Western Continents

North America

Canada, Costa Rica, Cuba, Mexico, Panama, USA

Canada, USA

South America

Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Queensland, Victoria

All about Gneiss and Granite Properties

Know all about Gneiss and Granite properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Granite belongs to Igneous Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Granite is Granular, Phaneritic. Gneiss appears Foliated and Granite appears Veined or Pebbled. The luster of Gneiss is dull while that of Granite is dull to grainy with sporadic parts pearly and vitreous. Gneiss is available in black, brown, pink, red, white colors whereas Granite is available in black, grey, orange, pink, white colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Granite are curling, gemstone, laboratory bench tops, tombstones, used in aquariums.