Definition
It is a metamorphic magnesium rich rock because it is composed of the mineral talc
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
History
Origin
USA
-
Discoverer
Unknown
Johann Gottlob Lehmann
Etymology
From 17th century, because of its greasy feel and use like a soap
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,
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Polished
Clastic, Splintery
Color
Black, Black to Grey, Green, Grey
Black, Brown, Buff, Green, Grey, Red, Yellow
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull, Banded and Foilated
Muddy
Architecture
Interior Uses
Bathrooms, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Manufacture of Magnesium and Dolomite Refractories
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Medical Industry
Taken as a Supplement for Calcium or Magnesium
-
Antiquity Uses
Artifacts, Jewellery, Monuments, Sculpture
Artifacts, Sculpture
Other Uses
Commercial Uses
Cemetery Markers, Creating Artwork, Gemstone, Jewelry, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Production of Lime, Source of Magnesia (MgO)
Creating Artwork, Pottery
Types
Metamorphic rock
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Features
Host Rock for Lead
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
Christ the Redeemer in Rio de Janeiro, Stonehenge in English county of Wiltshire
Jantar Mantar in India
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
Soapstone is a talc-schist, which is a type of metamorphic rock and it is largely composed of the mineral talc and is thus rich inmagnesium.
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.
Composition
Mineral Content
Albite, Apatite, Biotite, Calcite, Carbonate, Clay Minerals, Hornblende, Ilmenite, Micas, Plagioclase, Pyroxene, Quartz
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
CaO, Mg, MgO
Ca, Fe, Mg, Silicon Dioxide, Sodium
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal 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
13
1
7
👆🏻
Grain Size
Fine Grained
Very fine-grained
Fracture
Conchoidal
-
Streak
Black
White
Porosity
Less Porous
Highly Porous
Luster
Greasy
Dull
Compressive Strength
225.00 N/mm295.00 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
Slaty
Toughness
1
2.6
Specific Gravity
2.862.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm32.4-2.8 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.88 kJ/Kg K0.39 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Japan, North Korea, Russia, Saudi Arabia, Singapore, South Korea, Sri Lanka, Tajikistan, Thailand
Bangladesh, China, India, Russia
Africa
Egypt, Ethiopia, Ghana, South Africa, Western Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Austria, England, Finland, France, Germany, Greece, Spain, Sweden, Switzerland, United Kingdom
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Others
-
-
Deposits in Western Continents
North America
Canada, USA
USA
South America
Colombia
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
Central Australia, New Zealand, Queensland
New South Wales, New Zealand, Queensland, Victoria, Western Australia