Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture
Origin
Unknown
Tonale, Italy
Discoverer
Unknown
Unknown
Etymology
From French anorthose plagioclase + -ite1
From Tonale Pass, northern Italy, + -ite1
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Phaneritic
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Black, Brown, Light to Dark Grey, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Banded and Foilated
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Sculpture
Commercial Uses
Creating Artwork, Curling
Cemetery Markers, Creating Artwork
Types
Proterozoic Anorthosite and Archean Anorthosite
Dacite
Features
Generally rough to touch, Is one of the oldest rock
Is one of the oldest rock, Typically speckled black and white.
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
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.
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes tonalite with quartz as major mineral.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
NaCl, CaO, MgO, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Wind Erosion
Wind Erosion
Grain Size
Coarse Grained
Medium to Fine Coarse Grained
Fracture
Irregular
Conchoidal
Streak
White
Bluish Black
Porosity
Less Porous
Very Less Porous
Luster
Pearly to Subvitreous
Subvitreous to Dull
Cleavage
Irregular
Not Available
Toughness
Not Available
2.1
Specific Gravity
2.62-2.82
2.86-3
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.73 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
Not Yet Found
Africa
Not Yet Found
Egypt
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Finland, Germany, Italy, Romania, Sweden, Turkey
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
South America
Bolivia, Colombia
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New Zealand, South Australia, Western Australia