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