Definition
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Discoverer
Unknown
Johann Gottlob Lehmann
Etymology
From Greek pikros bitter + -ite, 19th century
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
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Earthy, Rough
Clastic, Splintery
Color
Black, Brown, Green, Grey, Pink, White, Yellow
Black, Brown, Buff, Green, Grey, Red, Yellow
Durability
Durable
Durable
Appearance
Rough and Shiny
Muddy
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
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.
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture
Commercial Uses
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Creating Artwork, Pottery
Types
Oceanite
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
Famous Monuments
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Jantar Mantar in India
Formation
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.
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.
Mineral Content
Biotite, Olivine, Plagioclase, Pyrrhotite
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
Al, CaO, Carbon Dioxide, Mg, MgO
Ca, Fe, Mg, Silicon Dioxide, Sodium
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
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Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Fine Grained
Very fine-grained
Streak
White, Greenish White or Grey
White
Porosity
Less Porous
Highly Porous
Luster
Subvitreous to Dull
Dull
Specific Gravity
2.75-2.92
2.2-2.8
Transparency
Opaque
Opaque
Density
1.5-2.5 g/cm3
2.4-2.8 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
India, Russia
Bangladesh, China, India, Russia
Africa
South Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Iceland
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
North America
Canada, USA
USA
South America
Brazil
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
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New South Wales, New Zealand, Queensland, Victoria, Western Australia
Picrite vs Shale 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. Picrite vs Shale characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Picrite and Properties of Shale. Learn more about Picrite vs Shale in the next section. The interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration whereas the interior uses of Shale include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Picrite and Shale, they have various applications in construction industry. The uses of Picrite in construction industry 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. and that of Shale include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Picrite and Shale
Here you can know more about Picrite and Shale. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Picrite and Shale consists of mineral content and compound content. The mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite and mineral content of Shale includes Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides. You can also check out the list of all Igneous Rocks. When we have to compare Picrite vs Shale, the texture, color and appearance plays an important role in determining the type of rock. Picrite is available in black, brown, green, grey, pink, white, yellow colors whereas, Shale is available in black, brown, buff, green, grey, red, yellow colors. Appearance of Picrite is Rough and Shiny and that of Shale is Muddy. Properties of rock is another aspect for Picrite vs Shale. The hardness of Picrite is 6.8 and that of Shale is 3. The types of Picrite are Oceanite whereas types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Picrite and Shale is white, greenish white or grey. The specific heat capacity of Picrite is 0.88 kJ/Kg K and that of Shale is 0.39 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Picrite is heat resistant whereas Shale is heat resistant, impact resistant.