Nephelinite

Anorthosite

Nephelinite and Anorthosite

Nephelinite

Anorthosite

Add ⊕

Definition

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

Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase

History

Origin

Brazil

Discoverer

Unknown

Etymology

from French néphéline, from Greek nephelē

From French anorthose plagioclase + -ite1

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Medium Hardness Rock

Family

Group

Plutonic

Other Categories

Fine Grained Rock, Opaque Rock

Coarse Grained Rock, Opaque Rock

Texture

Aphanitic

Foliated, Glassy

Color

Black, Brown, Green, Grey, White

Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Skeletal

Layered, Banded, Veined and Shiny

Uses

Architecture

Interior Uses

Decorative Aggregates, Homes, Interior Decoration

Decorative Aggregates, Floor Tiles, Homes, Interior Decoration

Exterior Uses

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

As Building Stone, As Facing Stone, Garden Decoration

Other Architectural Uses

Curbing

Industry

Construction Industry

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

As Dimension Stone, Cement Manufacture, for Road Aggregate

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Sculpture, Small Figurines

Other Uses

Commercial Uses

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

Creating Artwork, Curling

Types

Peralkaline Nephelinite

Proterozoic Anorthosite and Archean Anorthosite

Features

Host Rock for Lead

Generally rough to touch, Is one of the oldest rock

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

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.

Anorthosite is a phaneritic, intrusive igneous rock which is characterized by a predominance of plagioclase feldspar which is almost 90–100%, and a minimal mafic component.

Composition

Mineral Content

Clinopyroxene, Nepheline, Plagioclase

Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene

Compound Content

Ca, CaO, Carbon, Cl, MgO

Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Contact Metamorphism

Cataclastic Metamorphism, Contact Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Water Erosion, Wind Erosion

Chemical Erosion, Wind Erosion

Properties

Physical Properties

Hardness

6.55-6

1 7

👆🏻

Grain Size

Fine Grained

Coarse Grained

Fracture

Flat

Irregular

Streak

White

Porosity

Less Porous

Luster

Vitreous to Metallic

Pearly to Subvitreous

Compressive Strength

35.00 N/mm²180.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

2.7

Specific Gravity

2.4-2.92.62-2.82

0 8.4

👆🏻

Transparency

Opaque

Translucent

Density

2.5-3 g/cm³2.7-4 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.88 kJ/Kg K0.84 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

Japan

Africa

Rwanda, Tanzania

Europe

Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic

Others

Hawaii Islands

Deposits in Western Continents

North America

Canada, USA

Canada

South America

Colombia

Bolivia, Colombia

Deposits in Oceania Continent

Australia

Central Australia, South Australia, Western Australia

All about Nephelinite and Anorthosite Properties

Know all about Nephelinite and Anorthosite properties here. All properties of rocks are important as they define the type of rock and its application. Nephelinite and Anorthosite belong to Igneous Rocks.Texture of Nephelinite is Aphanitic whereas that of Anorthosite is Foliated, Glassy. Nephelinite appears Skeletal and Anorthosite appears Layered, Banded, Veined and Shiny. The luster of Nephelinite is vitreous to metallic while that of Anorthosite is pearly to subvitreous. Nephelinite is available in black, brown, green, grey, white colors whereas Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors. The commercial uses of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo) and that of Anorthosite are creating artwork, curling.