Definition
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Origin
Hawaii Islands
New Zealand
Discoverer
Unknown
Ferdinand von Hochstetter
Etymology
From Greek pikros bitter + -ite, 19th century
From the name of Dun Mountain, New Zealand, + -ite1
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Earthy, Rough
Phaneritic
Color
Black, Brown, Green, Grey, Pink, White, Yellow
Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Shiny
Rough and Shiny
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
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.
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Features
Host Rock for Lead
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Archaeological Significance
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.
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Mineral Content
Biotite, Olivine, Plagioclase, Pyrrhotite
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Compound Content
Al, CaO, Carbon Dioxide, Mg, MgO
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
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
Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Fine Grained
Coarse Grained
Fracture
Uneven
Irregular
Streak
White, Greenish White or Grey
White
Porosity
Less Porous
Less Porous
Luster
Subvitreous to Dull
Shiny
Specific Gravity
2.75-2.92
3-3.01
Transparency
Opaque
Translucent to Opaque
Density
1.5-2.5 g/cm3
2.84-2.85 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
Africa
South Africa
Morocco, South Africa
Europe
Iceland
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Argentina, Brazil, Colombia, Ecuador, Venezuela
Deposits in Oceania Continent
Australia
-
New Zealand, Western Australia
Picrite vs Dunite 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 Dunite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Picrite and Properties of Dunite. Learn more about Picrite vs Dunite in the next section. The interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration whereas the interior uses of Dunite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Picrite and Dunite, 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 Dunite include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Picrite and Dunite
Here you can know more about Picrite and Dunite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Picrite and Dunite consists of mineral content and compound content. The mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite and mineral content of Dunite includes Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Picrite vs Dunite, 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, Dunite is available in dark greenish - grey colors. Appearance of Picrite is Rough and Shiny and that of Dunite is Rough and Shiny. Properties of rock is another aspect for Picrite vs Dunite. The hardness of Picrite is 6.8 and that of Dunite is 3.5-4. The types of Picrite are Oceanite whereas types of Dunite are Dunite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Picrite and Dunite is white, greenish white or grey. The specific heat capacity of Picrite is 0.88 kJ/Kg K and that of Dunite is 1.25 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 Dunite is heat resistant, pressure resistant, wear resistant.