Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Discoverer
Unknown
Unknown
Etymology
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Splintery
Clastic or Non-Clastic
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Grey, White, Yellow
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Powder
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
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
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Pottery
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
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Not Available
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Archaeological Significance
Famous Monuments
Jantar Mantar in India
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Formation
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Calcite, Clay, Clay Minerals, Quartz, Sand
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
Ca, NaCl, CaO
Types of Metamorphism
Not Applicable
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Very fine-grained
Very fine-grained
Fracture
Not Available
Not Available
Porosity
Highly Porous
Highly Porous
Compressive Strength
Not Available
Cleavage
Slaty
Non-Existent
Specific Gravity
2.2-2.8
2.3-2.4
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
2.49-2.50 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
England, France, Germany, Spain, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Colombia
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Adelaide, New Zealand, Queensland, Tonga, Victoria, Yorke Peninsula
All about Shale and Chalk Properties
Know all about Shale and Chalk properties here. All properties of rocks are important as they define the type of rock and its application. Shale and Chalk belong to Sedimentary Rocks.Texture of Shale is Clastic, Splintery whereas that of Chalk is Clastic or Non-Clastic. Shale appears Muddy and Chalk appears Soft. The luster of Shale and Chalk is dull. Shale is available in black, brown, buff, green, grey, red, yellow colors whereas Chalk is available in grey, white, yellow colors. The commercial uses of Shale are creating artwork, pottery and that 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.