Definition
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Origin
New Zealand
Unknown
Discoverer
Ferdinand von Hochstetter
Unknown
Etymology
From the name of Dun Mountain, New Zealand, + -ite1
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Plutonic
Not Applicable
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Banded, Rough
Color
Dark Greenish - Grey
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Shiny
Glassy or Pearly
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Not Available
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Used
Not Yet Used
Formation
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
Mineral Content
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Quartz, Silicon
Compound Content
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Not Applicable
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Chemical Erosion
Grain Size
Coarse Grained
Very fine-grained
Fracture
Irregular
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Shiny
Waxy and Dull
Cleavage
Imperfect
Non-Existent
Specific Gravity
3-3.01
2.5-2.8
Transparency
Translucent to Opaque
Translucent to Opaque
Density
2.84-2.85 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Morocco, South Africa
Kenya, Morocco, South Africa, Tanzania
Europe
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland, Venezuela
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
Not Yet Found
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, USA
Canada, Mexico, USA
South America
Argentina, Brazil, Colombia, Ecuador, Venezuela
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Dunite vs Chert 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. Dunite vs Chert characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Dunite and Properties of Chert. Learn more about Dunite vs Chert in the next section. The interior uses of Dunite include Decorative aggregates and Interior decoration whereas the interior uses of Chert include Decorative aggregates and Homes. Due to some exceptional properties of Dunite and Chert, they have various applications in construction industry. The uses of Dunite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar and that of Chert include Arrowheads, Construction aggregate, Cutting tool, Spear points.
More about Dunite and Chert
Here you can know more about Dunite and Chert. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Dunite and Chert consists of mineral content and compound content. The mineral content of Dunite includes Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene and mineral content of Chert includes Quartz, Silicon. You can also check out the list of all Igneous Rocks. When we have to compare Dunite vs Chert, the texture, color and appearance plays an important role in determining the type of rock. Dunite is available in dark greenish - grey colors whereas, Chert is available in black, brown, green, grey, red, white colors. Appearance of Dunite is Rough and Shiny and that of Chert is Glassy or Pearly. Properties of rock is another aspect for Dunite vs Chert. The hardness of Dunite is 3.5-4 and that of Chert is 6.5-7. The types of Dunite are Not Available whereas types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Dunite and Chert is white. The specific heat capacity of Dunite is 1.25 kJ/Kg K and that of Chert is 0.74 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Dunite is heat resistant, pressure resistant, wear resistant whereas Chert is heat resistant, impact resistant, pressure resistant, wear resistant.