Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Origin
France
New Zealand
Discoverer
Unknown
Ferdinand von Hochstetter
Etymology
From French, Latin lignum wood + -ite1
From the name of Dun Mountain, New Zealand, + -ite1
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Phaneritic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Dark Greenish - Grey
Durability
Durable
Durable
Appearance
Veined or Pebbled
Rough and Shiny
Interior Uses
-
Decorative Aggregates, Interior Decoration
Exterior Uses
-
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
for Road Aggregate, Steel Production
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, Small Figurines
Commercial Uses
Electricity Generation
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Dunite
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
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
Coal formation takes place due to accumulation of plant debris in a swamp environment. The Coal formation process continues, as peat turns into lignite brown or black coal at increasing heat and pressure.
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Mineral Content
-
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Coarse Grained
Fracture
Conchoidal
Irregular
Porosity
Highly Porous
Less Porous
Luster
Dull to Vitreous to Submetallic
Shiny
Specific Gravity
1.1-1.4
3-3.01
Transparency
Opaque
Translucent to Opaque
Density
800-801 g/cm3
2.84-2.85 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Morocco, South Africa
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Brazil, Chile, Colombia, Venezuela
Argentina, Brazil, Colombia, Ecuador, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New Zealand, Western Australia
Lignite 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. Lignite vs Dunite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Lignite and Properties of Dunite. Learn more about Lignite vs Dunite in the next section. The interior uses of Lignite include whereas the interior uses of Dunite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Lignite and Dunite, they have various applications in construction industry. The uses of Lignite in construction industry include For road aggregate, Steel production 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 Lignite and Dunite
Here you can know more about Lignite and Dunite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Lignite and Dunite consists of mineral content and compound content. The mineral content of Lignite includes 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 Lignite vs Dunite, the texture, color and appearance plays an important role in determining the type of rock. Lignite is available in black, brown, dark brown, grey, light to dark grey colors whereas, Dunite is available in dark greenish - grey colors. Appearance of Lignite is Veined or Pebbled and that of Dunite is Rough and Shiny. Properties of rock is another aspect for Lignite vs Dunite. The hardness of Lignite is 1 and that of Dunite is 3.5-4. The types of Lignite are Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite 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 Lignite is black while that of Dunite is white. The specific heat capacity of Lignite is 1.26 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.Lignite is heat resistant whereas Dunite is heat resistant, pressure resistant, wear resistant.