Nephelinite

Porphyry

Nephelinite and Porphyry

Nephelinite

Porphyry

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1 Definition

1.1 Definition

Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).

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

1.2 History

1.2.1 Origin

Brazil

Egypt

1.2.2 Discoverer

Unknown

1.3 Etymology

from French néphéline, from Greek nephelē

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

1.4 Class

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Plutonic

1.6 Other Categories

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Aphanitic

Porphyritic

2.2 Color

Black, Brown, Colourless, Green, Grey, White

Black, Brown, Colourless, Green, Grey, Red, Rust, 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

Skeletal

Dull

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Decorative Aggregates, Homes, Interior Decoration

Decorative Aggregates, Interior Decoration

3.1.2 Exterior Uses

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

Garden Decoration, Paving Stone

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

Construction Aggregate

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Monuments, Sculpture

3.4 Other Uses

3.4.1 Commercial Uses

Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)

Creating Artwork, Gemstone, Jewelry

4 Types

4.1 Types

Peralkaline Nephelinite

Rhomb Porphyry

4.2 Features

Host Rock for Lead

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

4.3 Archaeological Significance

4.3.1 Monuments

Used

4.3.2 Famous Monuments

Data Not Available

4.3.3 Sculpture

Used

4.3.4 Famous Sculptures

Data Not Available

4.3.5 Pictographs

Not Used

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Used

4.4 Fossils

Absent

5 Formation

5.1 Formation

Nephelinite 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.

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.

5.2 Composition

5.2.1 Mineral Content

Clinopyroxene, Nepheline, Plagioclase

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

5.2.2 Compound Content

Ca, CaO, Carbon, Cl, MgO

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

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Contact Metamorphism

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

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering, Not Registered

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Water Erosion, Wind Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6.56-7

1 7

6.1.2 Grain Size

Fine Grained

6.1.3 Fracture

Flat

Irregular

6.1.4 Streak

White

6.1.5 Porosity

Less Porous

6.1.6 Luster

Vitreous to Metallic

Dull

6.1.7 Compressive Strength

35.00 N/mm²NA

0.15 450

6.1.8 Cleavage

Imperfect

6.1.9 Toughness

2.7

1.7

6.1.10 Specific Gravity

2.4-2.92.5-4

0 8.4

6.1.11 Transparency

Opaque

Translucent to Opaque

6.1.12 Density

2.5-3 g/cm³2.5-2.52 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

0.88 kJ/Kg KNA

0.14 3.2

6.2.2 Resistance

Heat Resistant

Heat Resistant, Impact Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

Japan

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

7.1.2 Africa

Rwanda, Tanzania

Egypt, Ethiopia, Ghana, South Africa

7.1.3 Europe

Not Yet Found

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

7.1.4 Others

Hawaii Islands

Greenland

7.2 Deposits in Western Continents

7.2.1 North America

Canada, USA

Canada, Cuba, Jamaica, USA

7.2.2 South America

Colombia

Bolivia, Brazil, Colombia, Ecuador, Paraguay

7.3 Deposits in Oceania Continent

7.3.1 Australia

Not Yet Found

New South Wales, New Zealand, Western Australia

All about Nephelinite and Porphyry Properties

Know all about Nephelinite and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Nephelinite and Porphyry belong to Igneous Rocks.Texture of Nephelinite is Aphanitic whereas that of Porphyry is Porphyritic. Nephelinite appears Skeletal and Porphyry appears Dull. The luster of Nephelinite is vitreous to metallic while that of Porphyry is dull. Nephelinite is available in black, brown, colourless, green, grey, white colors whereas Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors. The commercial uses of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo) and that of Porphyry are creating artwork, gemstone, jewelry.