Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Greenschist is a metamorphic rock that is formed under lowest temperatures and pressures and is usually produced by regional metamorphism
History
Origin
-
-
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 minerals such as chlorite, serpentine, and epidote, and platy minerals such as muscovite and platy serpentine which are green in color
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Foliated, Platy
Color
Grey, White, Yellow
Dark Greenish - Grey, Green
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Soft
Layered and Shiny
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Powder
Curbing
Industry
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, Building houses or walls, Cement Manufacture, Cutting Tool, for Road Aggregate, Roadstone
Medical Industry
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-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Other Uses
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
Blackboards, Manufacture of tools, Writing Slates
Types
Chalk Marl and Marl
Metamorphic rock
Features
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Easily splits into thin plates, Smooth to touch
Archaeological Significance
Monuments
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-
Famous Monuments
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-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
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-
Figurines
-
-
Fossils
Present
Absent
Formation
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Greenschist is medium grade metamorphic rock, formed by the metamorphosis of mudstone or shale, or some types of igneous rock, when it is subjected to higher temperatures and pressures.
Composition
Mineral Content
Calcite, Clay, Clay Minerals, Quartz, Sand
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Serpentine, Sillimanite, Staurolite, Talc
Compound Content
Ca, NaCl, CaO
CaO, Carbon Dioxide, MgO
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion
Physical Properties
Hardness
13.5-4
1
7
👆🏻
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
-
Conchoidal
Streak
White
White
Porosity
Highly Porous
Highly Porous
Luster
Dull
Shiny
Compressive Strength
5.00 N/mm2160.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Slaty
Toughness
1
1.5
Specific Gravity
2.3-2.42.5-2.9
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.49-2.50 g/cm32.8-2.9 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.90 kJ/Kg K0.84 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Impact Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
England, France, Germany, Spain, United Kingdom
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Others
-
-
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Colombia
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
New South Wales, New Zealand, Queensland