Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Discoverer
Unknown
Unknown
Etymology
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
From French anorthose plagioclase + -ite1
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Foliated, Glassy
Color
Grey, White, Yellow
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Durability
Durable
Durable
Appearance
Soft
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Powder
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, raw material for manufacture of quicklime and slaked lime, Source of calcium
As Dimension Stone, Cement Manufacture, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture, Small Figurines
Commercial Uses
Alumina Refineries, Creating Artwork, Drawing on blackboards, Gymnasts, athletes and mountain climbers use for grip, In aquifers, Paper Industry, Production of Lime, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Whiting, Whiting material in toothpaste, paint and paper
Creating Artwork, Curling
Types
Chalk Marl and Marl
Proterozoic Anorthosite and Archean Anorthosite
Features
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Formation
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
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.
Mineral Content
Calcite, Clay, Clay Minerals, Quartz, Sand
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Compound Content
Ca, NaCl, CaO
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Types of Metamorphism
-
Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Chemical Erosion, Wind Erosion
Grain Size
Very fine-grained
Coarse Grained
Porosity
Highly Porous
Less Porous
Luster
Dull
Pearly to Subvitreous
Specific Gravity
2.3-2.4
2.62-2.82
Transparency
Opaque
Translucent
Density
2.49-2.50 g/cm3
2.7-4 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
-
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
-
Europe
England, France, Germany, Spain, United Kingdom
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Colombia
Bolivia, Colombia
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
Central Australia, South Australia, Western Australia
All about Chalk and Anorthosite Properties
Know all about Chalk and Anorthosite properties here. All properties of rocks are important as they define the type of rock and its application. Chalk belongs to Sedimentary Rocks while Anorthosite belongs to Igneous Rocks.Texture of Chalk is Clastic or Non-Clastic whereas that of Anorthosite is Foliated, Glassy. Chalk appears Soft and Anorthosite appears Layered, Banded, Veined and Shiny. The luster of Chalk is dull while that of Anorthosite is pearly to subvitreous. Chalk is available in grey, white, yellow colors whereas Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors. The commercial uses of Chalk are alumina refineries, creating artwork, drawing on blackboards, gymnasts, athletes and mountain climbers use for grip, in aquifers, paper industry, production of lime, raw material for manufacture of quicklime, slaked lime, soil conditioner, whiting, whiting material in toothpaste, paint and paper and that of Anorthosite are creating artwork, curling.