Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Discoverer
Unknown
Unknown
Etymology
From French anorthose plagioclase + -ite1
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Plutonic
Not Applicable
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Banded, Rough
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Glassy or Pearly
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork, Curling
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Proterozoic Anorthosite and Archean Anorthosite
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Generally rough to touch, Is one of the oldest rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Figurines
Used
Not Yet 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.
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Quartz, Silicon
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Not Applicable
Types of Weathering
Biological Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion
Grain Size
Coarse Grained
Very fine-grained
Fracture
Irregular
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Pearly to Subvitreous
Waxy and Dull
Compressive Strength
Not Available
Cleavage
Irregular
Non-Existent
Toughness
Not Available
1.5
Specific Gravity
2.62-2.82
2.5-2.8
Transparency
Translucent
Translucent to Opaque
Density
2.7-4 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Not Yet Found
Kenya, Morocco, South Africa, Tanzania
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
Not Yet Found
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada
Canada, Mexico, USA
South America
Bolivia, Colombia
Bolivia, Brazil
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New South Wales, Queensland, South Australia, Western Australia
All about Anorthosite and Chert Properties
Know all about Anorthosite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Anorthosite belongs to Igneous Rocks while Chert belongs to Sedimentary Rocks.Texture of Anorthosite is Foliated, Glassy whereas that of Chert is Banded, Rough. Anorthosite appears Layered, Banded, Veined and Shiny and Chert appears Glassy or Pearly. The luster of Anorthosite is pearly to subvitreous while that of Chert is waxy and dull. Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors whereas Chert is available in black, brown, green, grey, red, white colors. The commercial uses of Anorthosite are creating artwork, curling and that of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.