Granite

Porphyry

Granite and Porphyry

Granite

Porphyry

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Definition

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

Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix

History

Origin

Egypt

Discoverer

Alexander von Humboldt

Unknown

Etymology

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

From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Plutonic

Other Categories

Coarse Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Granular, Phaneritic

Porphyritic

Color

Black, Grey, Orange, Pink, White

Black, Brown, Green, Grey, Red, Rust, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Veined or Pebbled

Dull

Uses

Architecture

Interior Uses

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

Decorative Aggregates, Interior Decoration

Exterior Uses

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

Garden Decoration, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone

Construction Aggregate

Medical Industry

Antiquity Uses

Monuments, Sculpture, Small Figurines

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

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

Creating Artwork, Gemstone, Jewelry

Types

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

Rhomb Porphyry

Features

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

Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny

Archaeological Significance

Monuments

Famous Monuments

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

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

Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.

Composition

Mineral Content

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

Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica

Compound Content

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

Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering

Biological Weathering, Chemical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Sea Erosion, Water Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

6-76-7

1 7

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Grain Size

Large and Coarse Grained

Fine Grained

Fracture

Irregular

Streak

White

Porosity

Less Porous

Luster

Dull to Grainy with Sporadic parts Pearly and Vitreous

Dull

Compressive Strength

175.00 N/mm²150.00 N/mm²

0.15 450

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Cleavage

Toughness

1.7

Specific Gravity

2.6-2.72.5-4

0 8.4

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Transparency

Opaque

Translucent to Opaque

Density

2.65-2.75 g/cm³2.5-2.52 g/cm³

0 1400

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Thermal Properties

Specific Heat Capacity

0.79 kJ/Kg K0.71 kJ/Kg K

0.14 3.2

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Resistance

Heat Resistant, Wear Resistant

Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

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

China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam

Africa

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

Egypt, Ethiopia, Ghana, South Africa

Europe

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

Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland

Others

Greenland

Deposits in Western Continents

North America

Canada, USA

Canada, Cuba, Jamaica, USA

South America

Bolivia, Brazil, Colombia, Ecuador, Paraguay

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Western Australia

All about Granite and Porphyry Properties

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