Definition
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
  
Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth
  
History
  
  
Origin
New Zealand
  
Ethiopia
  
Discoverer
Unknown
  
Obsius
  
Etymology
From Greek mulōn mill + -ite
  
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
  
Class
Metamorphic Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Not Applicable
  
Volcanic
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Opaque Rock
  
Texture
Foliated
  
Glassy
  
Color
Black to Grey
  
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull, Banded and Foilated
  
Shiny
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
  
Garden Decoration
  
Other Architectural Uses
Curbing
  
Not Yet Used
  
Industry
  
  
Construction Industry
for Road Aggregate, Landscaping, Roadstone
  
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
Medical Industry
Not Yet Used
  
Surgery
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Jewellery
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone, Jewelry
  
Creating Artwork, Mirror, Used in aquariums
  
Types
Blastomylonites, Ultramylonites and Phyllonites
  
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
  
Features
Surfaces are often shiny
  
Blocks negativity, Helps to protect against depression
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Not Applicable
  
Sculpture
Used
  
Not Yet Used
  
Famous Sculptures
Data Not Available
  
Not Applicable
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
Formation
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
  
When the lava is released from volcano, it undergoes a very rapid cooling which freezes the mechanisms of crystallization. The result is a volcanic glass with a uniform smooth texture.
  
Composition
  
  
Mineral Content
Porphyroblasts
  
Not Available
  
Compound Content
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
  
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, 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, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
  
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Physical Properties
  
  
Hardness
3-4
  
5-5.5
  
Grain Size
Fine Grained
  
Not Applicable
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Highly Porous
  
Very Less Porous
  
Luster
Shiny
  
Vitreous
  
Cleavage
Conchoidal
  
Non-Existent
  
Toughness
Not Available
  
Not Available
  
Specific Gravity
2.97-3.05
  
2.6-2.7
  
Transparency
Opaque
  
Translucent
  
Density
2.6-4.8 g/cm3
  
2.6 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
1.50 kJ/Kg K
  
3
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Indonesia, Saudi Arabia, South Korea
  
Afghanistan, Indonesia, Japan, Russia
  
Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
  
Kenya
  
Europe
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
  
Greece, Hungary, Iceland, Italy, Turkey
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, Mexico, USA
  
South America
Not Yet Found
  
Argentina, Chile, Ecuador, Peru
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New Zealand
  
Mylonite vs Obsidian 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. Mylonite vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Mylonite and Properties of Obsidian. Learn more about Mylonite vs Obsidian in the next section. The interior uses of Mylonite include Decorative aggregates and Interior decoration whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Mylonite and Obsidian, they have various applications in construction industry. The uses of Mylonite in construction industry include For road aggregate, Landscaping, Roadstone and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Mylonite and Obsidian
Here you can know more about Mylonite and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Mylonite and Obsidian consists of mineral content and compound content. The mineral content of Mylonite includes Porphyroblasts and mineral content of Obsidian is not available. You can also check out the list of all Metamorphic Rocks. When we have to compare Mylonite vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Mylonite is available in black to grey colors whereas, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Mylonite is Dull, Banded and Foilated and that of Obsidian is Shiny. Properties of rock is another aspect for Mylonite vs Obsidian. The hardness of Mylonite is 3-4 and that of Obsidian is 5-5.5. The types of Mylonite are Blastomylonites, Ultramylonites and Phyllonites whereas types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Mylonite and Obsidian is white. The specific heat capacity of Mylonite is 1.50 kJ/Kg K and that of Obsidian is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Mylonite is heat resistant, impact resistant, pressure resistant whereas Obsidian is heat resistant, impact resistant.