Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
A water-soluble mineral sediment resulting from concentration and crystallization by evaporation from an aqueous solution
History
Origin
-
USA
Discoverer
Johann Gottlob Lehmann
Usiglio
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 a sediment left after the evaporation
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Clastic, Splintery
Earthy
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Green, Grey, Silver, White
Maintenance
More
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Muddy
Glassy, Vesicular and Foilated
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Sculpture
Artifacts
Other Uses
Commercial Uses
Creating Artwork, Pottery
Used in the manufacture of Ceramic Powder, Used in the preparation of Sulfuric Acid and Silicon Diborite
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Sedimentary rock
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Generally rough to touch, Splintery, Veined
Archaeological Significance
Monuments
-
-
Famous Monuments
Jantar Mantar in India
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Present
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.
Evaporite is water-soluble mineral sediment which forms from concentration and crystallization by evaporation from an aqueous solution.
Composition
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Calcite, Cancrinite, Gypsum, Kyanite, Magnetite
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
CaMg(CO3)2, CaO, Calcium Sulfate, KCl, MgO, NaCl
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
-
Physical Properties
Hardness
32-3
1
7
👆🏻
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
-
Conchoidal
Streak
White
White
Porosity
Highly Porous
Less Porous
Luster
Dull
Subvitreous to Dull
Compressive Strength
95.00 N/mm2225.00 N/mm2
0.15
450
👆🏻
Cleavage
Slaty
Perfect
Toughness
2.6
-
Specific Gravity
2.2-2.82.86-2.99
0
8.4
👆🏻
Transparency
Opaque
Translucent
Density
2.4-2.8 g/cm32.8-2.9 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.39 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
-
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
-
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
United Kingdom
Others
-
-
Deposits in Western Continents
North America
USA
USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Colombia, Paraguay
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Central Australia, Western Australia