Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
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 Pelos or clay in Greek
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Clastic, Splintery
Foliated
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts
Commercial Uses
Creating Artwork, Pottery
Commemorative Tablets, Creating Artwork
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
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Jantar Mantar in India
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Albite, Chlorite, Quartz
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
Aluminium Oxide, CaO, MgO
Types of Metamorphism
Not Applicable
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
Not Available
Fibrous
Porosity
Highly Porous
Highly Porous
Compressive Strength
Not Available
Cleavage
Slaty
Not Available
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
3.4-3.7
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
0-300 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
Not Yet Found
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Western Africa
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Not Available
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Central Australia, Western Australia