Hornfels and Dunite
Definition
Definition
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
History
Origin
New Zealand
New Zealand
Discoverer
Unknown
Ferdinand von Hochstetter
Etymology
From German which means hornstone
From the name of Dun Mountain, New Zealand, + -ite1
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Texture
Granular, Platy
Phaneritic
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Dark Greenish - Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
Yes
Yes
Scratch Resistant
No
Yes
Stain Resistant
No
Yes
Wind Resistant
No
No
Acid Resistant
No
No
Appearance
Dull
Rough and Shiny
Uses
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
for Road Aggregate, 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
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Types
Types
Biotite hornfels
Not Available
Features
Smooth to touch
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
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Used
Used
Petroglyphs
Used
Used
Figurines
Not Yet Used
Used
Fossils
Absent
Absent
Formation
Formation
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Composition
Mineral Content
Andalusite
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Compound Content
Fe, Mg
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Transformation
Metamorphism
No
Yes
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Weathering
Yes
Yes
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
Yes
Yes
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Properties
Physical Properties
Hardness
2-3
3.5-4
Grain Size
Fine Grained
Coarse Grained
Fracture
Conchoidal
Irregular
Streak
Unknown
White
Porosity
Highly Porous
Less Porous
Luster
Shiny
Shiny
Compressive Strength
5.80 N/mm2
31
107.55 N/mm2
19
Cleavage
Perfect
Imperfect
Toughness
Not Yet Found
2.1
Specific Gravity
3.4-3.9
3-3.01
Transparency
Opaque
Translucent to Opaque
Density
0.25-0.30 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, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Reserves
Deposits in Eastern Continents
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
Africa
Cameroon, East Africa, Tanzania, Western Africa
Morocco, South Africa
Europe
United Kingdom
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
Bolivia, Brazil, Colombia, Ecuador
Argentina, Brazil, Colombia, Ecuador, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Western Australia
New Zealand, Western Australia
All about Hornfels and Dunite Properties
Know all about Hornfels and Dunite properties here. All properties of rocks are important as they define the type of rock and its application. Hornfels belongs to Metamorphic Rocks while Dunite belongs to Igneous Rocks.Texture of Hornfels is Granular, Platy whereas that of Dunite is Phaneritic. Hornfels appears Dull and Dunite appears Rough and Shiny. The luster of Hornfels and Dunite is shiny. Hornfels and Dunite are available in brown, dark greenish - grey, green, reddish brown colors. The commercial uses of Hornfels are cemetery markers, commemorative tablets, creating artwork and that of Dunite are creating artwork, gemstone, jewelry, source of chromite, platinum, nickel and garnet, source of diamonds.
|
||
|
||
|
