Definition
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
  
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
Unknown
  
Ethiopia
  
Discoverer
Unknown
  
Obsius
  
Etymology
From the mineral feldspathoid which is the main content of rock
  
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
  
Class
Igneous Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Soft Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Plutonic
  
Volcanic
  
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Opaque Rock
  
Texture
Earthy
  
Glassy
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull
  
Shiny
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Garden Decoration
  
Other Architectural Uses
Curbing
  
Not Yet Used
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
  
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
Medical Industry
Taken as a Supplement for Calcium or Magnesium
  
Surgery
  
Antiquity Uses
Artifacts, Monuments, Sculpture
  
Artifacts, Jewellery
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Creating Artwork, Mirror, Used in aquariums
  
Types
Not Available
  
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
  
Features
Host Rock for Lead
  
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
Foidolites is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
  
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
Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene
  
Not Available
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO
  
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, Hydrothermal Metamorphism, Impact Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Physical Properties
  
  
Hardness
1.5
  
5-5.5
  
Grain Size
Medium to Fine Coarse Grained
  
Not Applicable
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Very Less Porous
  
Luster
Subvitreous to Dull
  
Vitreous
  
Compressive Strength
Not Available
  
Cleavage
Perfect
  
Non-Existent
  
Toughness
Not Available
  
Not Available
  
Specific Gravity
2.86
  
2.6-2.7
  
Transparency
Translucent
  
Translucent
  
Density
Not Available
  
2.6 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
Not Available
  
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
Russia
  
Afghanistan, Indonesia, Japan, Russia
  
Africa
South Africa, Western Africa
  
Kenya
  
Europe
Not Yet Found
  
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
Not Yet Found
  
Argentina, Chile, Ecuador, Peru
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New Zealand
  
Foidolite 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. Foidolite vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Foidolite and Properties of Obsidian. Learn more about Foidolite vs Obsidian in the next section. The interior uses of Foidolite include Decorative aggregates and Interior decoration whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Foidolite and Obsidian, they have various applications in construction industry. The uses of Foidolite in construction industry include As dimension stone, Cement manufacture, For road aggregate and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Foidolite and Obsidian
Here you can know more about Foidolite and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Foidolite and Obsidian consists of mineral content and compound content. The mineral content of Foidolite includes Amphibole, Biotite, Feldspar, 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 Foidolite vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Foidolite is available in black, brown, colourless, green, grey, pink, white colors whereas, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Foidolite is Dull and that of Obsidian is Shiny. Properties of rock is another aspect for Foidolite vs Obsidian. The hardness of Foidolite is 1.5 and that of Obsidian is 5-5.5. The types of Foidolite 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 Foidolite and Obsidian is white. The specific heat capacity of Foidolite is Not Available 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.Foidolite is heat resistant, wear resistant whereas Obsidian is heat resistant, impact resistant.