Definition
Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance
  
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
  
History
  
  
Origin
France
  
New Zealand
  
Discoverer
Unknown
  
Ferdinand von Hochstetter
  
Etymology
From Latin varius, speckled, variegated
  
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
  
Family
  
  
Group
Volcanic
  
Plutonic
  
Other Categories
Opaque Rock
  
Coarse Grained Rock, Opaque Rock
  
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
  
Phaneritic
  
Color
Black, Brown, Light to Dark Grey
  
Dark Greenish - Grey
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
Yes
  
No
  
Appearance
Dull and Soft
  
Rough and Shiny
  
Architecture
  
  
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
Garden Decoration, Office Buildings
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
  
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, Sculpture
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
  
Types
Not Available
  
Not Available
  
Features
Has High structural resistance against erosion and climate, Very fine grained rock
  
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Used
  
Used
  
Fossils
Absent
  
Absent
  
Formation
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
  
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
  
Composition
  
  
Mineral Content
Olivine, Plagioclase, Pyroxene
  
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Coastal Erosion, Glacier Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
6
  
3.5-4
  
Grain Size
Not Applicable
  
Coarse Grained
  
Fracture
Conchoidal
  
Irregular
  
Streak
White to Grey
  
White
  
Porosity
Less Porous
  
Less Porous
  
Luster
Not Available
  
Shiny
  
Compressive Strength
37.50 N/mm2
  
27
107.55 N/mm2
  
19
Cleavage
Not Available
  
Imperfect
  
Toughness
2.3
  
2.1
  
Specific Gravity
2.8-3
  
3-3.01
  
Transparency
Opaque
  
Translucent to Opaque
  
Density
2.9-3.1 g/cm3
  
2.84-2.85 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.84 kJ/Kg K
  
15
1.25 kJ/Kg K
  
6
Resistance
Heat Resistant, Pressure Resistant, Wear 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, Venezuela
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, USA
  
South America
Brazil
  
Argentina, Brazil, Colombia, Ecuador, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
New Zealand, Western Australia
  
Variolite 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. Variolite vs Dunite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Variolite and Properties of Dunite. Learn more about Variolite vs Dunite in the next section. The interior uses of Variolite include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Dunite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Variolite and Dunite, they have various applications in construction industry. The uses of Variolite in construction industry include As dimension stone, Cobblestones, Rail track ballast, Roadstone 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 Variolite and Dunite
Here you can know more about Variolite and Dunite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Variolite and Dunite consists of mineral content and compound content. The mineral content of Variolite includes Olivine, Plagioclase, Pyroxene 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 Variolite vs Dunite, the texture, color and appearance plays an important role in determining the type of rock. Variolite is available in black, brown, light to dark grey colors whereas, Dunite is available in dark greenish - grey colors. Appearance of Variolite is Dull and Soft and that of Dunite is Rough and Shiny. Properties of rock is another aspect for Variolite vs Dunite. The hardness of Variolite is 6 and that of Dunite is 3.5-4. The types of Variolite are Not Available 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 Variolite is white to grey while that of Dunite is white. The specific heat capacity of Variolite is 0.84 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.Variolite is heat resistant, pressure resistant, wear resistant whereas Dunite is heat resistant, pressure resistant, wear resistant.