Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Origin
Unknown
Hawaii Islands
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 Greek pikros bitter + -ite, 19th century
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Splintery
Earthy, Rough
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Black, Brown, Colourless, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Appearance
Muddy
Rough and Shiny
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Countertops, Decorative Aggregates, 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
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, for Road Aggregate, Manufacture of Magnesium and Dolomite Refractories, Roadstone, Used for flooring, stair treads, borders and window sills.
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Pottery
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Oceanite
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Host Rock for Lead
Archaeological Significance
Famous Monuments
Jantar Mantar in India
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not 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.
Picrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
Al, CaO, Carbon Dioxide, Mg, MgO
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Not Available
Uneven
Streak
White
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Dull
Subvitreous to Dull
Specific Gravity
2.2-2.8
2.75-2.92
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
1.5-2.5 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
India, Russia
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
South Africa
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Iceland
Others
Not Yet Found
Not Yet Found
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
Not Yet Found
Shale vs Picrite Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Shale vs Picrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Shale and Properties of Picrite. Learn more about Shale vs Picrite in the next section. The interior uses of Shale include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Shale and Picrite, they have various applications in construction industry. The uses of Shale in construction industry include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar and that of Picrite include As a sintering agent in steel industry to process iron ore, Cement manufacture, For road aggregate, Manufacture of magnesium and dolomite refractories, Roadstone, Used for flooring, stair treads, borders and window sills..
More about Shale and Picrite
Here you can know more about Shale and Picrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Shale and Picrite consists of mineral content and compound content. The mineral content of Shale includes Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides and mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite. You can also check out the list of all Sedimentary Rocks. When we have to compare Shale vs Picrite, the texture, color and appearance plays an important role in determining the type of rock. Shale is available in black, brown, buff, green, grey, red, yellow colors whereas, Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors. Appearance of Shale is Muddy and that of Picrite is Rough and Shiny. Properties of rock is another aspect for Shale vs Picrite. The hardness of Shale is 3 and that of Picrite is 6.8. The types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale whereas types of Picrite are Oceanite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Shale is white while that of Picrite is white, greenish white or grey. The specific heat capacity of Shale is 0.39 kJ/Kg K and that of Picrite is 0.88 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Shale is heat resistant, impact resistant whereas Picrite is heat resistant.