Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
  
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
  
History
  
  
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 German Grauwacke, from grau grey + wacke
  
Class
Sedimentary Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Clastic, Splintery
  
Clastic
  
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
  
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
  
Maintenance
More
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
Yes
  
Acid Resistant
No
  
No
  
Appearance
Muddy
  
Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
  
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing, Whetstones
  
Industry
  
  
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Sculpture
  
Artifacts, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Pottery
  
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
  
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
  
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Jantar Mantar in India
  
Not Applicable
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Not Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Used
  
Used
  
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.
  
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
  
Composition
  
  
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
  
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
  
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
  
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Transformation
  
  
Metamorphism
No
  
No
  
Types of Metamorphism
Not Applicable
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Coastal Erosion, Sea Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
3
  
6-7
  
Grain Size
Very fine-grained
  
Angular and Fine
  
Fracture
Not Available
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Highly Porous
  
Highly Porous
  
Luster
Dull
  
Dull
  
Compressive Strength
95.00 N/mm
2
  
20
Not Available
  
Cleavage
Slaty
  
Perfect
  
Toughness
2.6
  
2.6
  
Specific Gravity
2.2-2.8
  
2.2-2.8
  
Transparency
Opaque
  
Opaque
  
Density
2.4-2.8 g/cm3
  
2.6-2.61 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.39 kJ/Kg K
  
23
Not Available
  
Resistance
Heat Resistant, Impact Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant
  
Deposits in Eastern Continents
  
  
Asia
Bangladesh, China, India, Russia
  
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
  
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
  
Namibia, Nigeria, South Africa
  
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
  
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
  
Others
Not Yet Found
  
Greenland
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, USA
  
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
  
Brazil
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
  
New South Wales, New Zealand