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
  
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
France
  
Ethiopia
  
Discoverer
Unknown
  
Obsius
  
Etymology
From Latin varius, speckled, variegated
  
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
  
Class
Igneous Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Volcanic
  
Volcanic
  
Other Categories
Opaque Rock
  
Opaque Rock
  
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
  
Glassy
  
Color
Black, Brown, Light to Dark 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
Yes
  
No
  
Appearance
Dull and Soft
  
Shiny
  
Architecture
  
  
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
Garden Decoration, Office Buildings
  
Garden Decoration
  
Other Architectural Uses
Curbing
  
Not Yet Used
  
Industry
  
  
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
  
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
Medical Industry
Not Yet Used
  
Surgery
  
Antiquity Uses
Artifacts, Monuments, Sculpture
  
Artifacts, Jewellery
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Creating Artwork, Mirror, Used in aquariums
  
Types
Not Available
  
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
  
Features
Has High structural resistance against erosion and climate, Very fine grained rock
  
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
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
  
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
Olivine, Plagioclase, Pyroxene
  
Not Available
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, 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
  
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Physical Properties
  
  
Hardness
6
  
5-5.5
  
Grain Size
Not Applicable
  
Not Applicable
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White to Grey
  
White
  
Porosity
Less Porous
  
Very Less Porous
  
Luster
Not Available
  
Vitreous
  
Compressive Strength
37.50 N/mm2
  
27
Cleavage
Not Available
  
Non-Existent
  
Toughness
2.3
  
Not Available
  
Specific Gravity
2.8-3
  
2.6-2.7
  
Transparency
Opaque
  
Translucent
  
Density
2.9-3.1 g/cm3
  
2.6 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.84 kJ/Kg K
  
15
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
India, Russia
  
Afghanistan, Indonesia, Japan, Russia
  
Africa
South Africa
  
Kenya
  
Europe
Iceland
  
Greece, Hungary, Iceland, Italy, Turkey
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, Mexico, USA
  
South America
Brazil
  
Argentina, Chile, Ecuador, Peru
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
New Zealand
  
Variolite 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. Variolite vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Variolite and Properties of Obsidian. Learn more about Variolite vs Obsidian in the next section. The interior uses of Variolite include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Variolite and Obsidian, 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 Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Variolite and Obsidian
Here you can know more about Variolite and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Variolite and Obsidian consists of mineral content and compound content. The mineral content of Variolite includes Olivine, Plagioclase, Pyroxene and mineral content of Obsidian is not available. You can also check out the list of all Igneous Rocks. When we have to compare Variolite vs Obsidian, 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, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Variolite is Dull and Soft and that of Obsidian is Shiny. Properties of rock is another aspect for Variolite vs Obsidian. The hardness of Variolite is 6 and that of Obsidian is 5-5.5. The types of Variolite are Not Available 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 Variolite is white to grey while that of Obsidian is white. The specific heat capacity of Variolite is 0.84 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.Variolite is heat resistant, pressure resistant, wear resistant whereas Obsidian is heat resistant, impact resistant.