Definition
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
  
Jasperoid is a rare, peculiar type of metasomatic alteration of rocks
  
History
  
  
Origin
Ethiopia
  
USA
  
Discoverer
Obsius
  
Unknown
  
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
  
From silica, the main mineral content of Jasperoid
  
Class
Igneous Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
Other Categories
Opaque Rock
  
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Glassy
  
Earthy
  
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
  
Black, Brown, Colourless, Green, Grey, Pink, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Shiny
  
Glassy or Pearly
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
  
Exterior Uses
Garden Decoration
  
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
  
Other Architectural Uses
Not Yet Used
  
Curbing
  
Industry
  
  
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics, Serves as an Oil and Gas Reservoir rock
  
Medical Industry
Surgery
  
Taken as a Supplement for Calcium or Magnesium
  
Antiquity Uses
Artifacts, Jewellery
  
Artifacts, Jewellery, Monuments, Sculpture
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
  
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
  
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
  
Not Available
  
Features
Blocks negativity, Helps to protect against depression
  
Host Rock for Lead, Traps for subsurface fluids like Oil and Natural Gas., Zinc and Copper Deposits
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Used
  
Famous Monuments
Not Applicable
  
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
  
Present
  
Formation
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.
  
Jasperoid is a rare and peculiar type of metasomatic alteration of rocks. It is formed by extreme alteration of wall rocks within a shear zone which may occur in sediments, andesites, trachytes and basalts.
  
Composition
  
  
Mineral Content
Not Available
  
Clay Minerals, Pyrite, Quartz, Sulfides
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
No
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Not Applicable
  
Erosion
Yes
  
No
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Not Applicable
  
Physical Properties
  
  
Hardness
5-5.5
  
3.5-4
  
Grain Size
Not Applicable
  
Medium to Fine Coarse Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Less Porous
  
Luster
Vitreous
  
Vitreous and Pearly
  
Compressive Strength
140.00 N/mm2
  
15
Cleavage
Non-Existent
  
Perfect
  
Toughness
Not Available
  
1
  
Specific Gravity
2.6-2.7
  
2.8-3
  
Transparency
Translucent
  
Transparent to Translucent
  
Density
2.6 g/cm3
  
2.8-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Impact Resistant
  
Heat Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
Afghanistan, Indonesia, Japan, Russia
  
China, India
  
Africa
Kenya
  
Morocco, Namibia
  
Europe
Greece, Hungary, Iceland, Italy, Turkey
  
Austria, Italy, Romania, Spain, Switzerland
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, Mexico, USA
  
Mexico, USA
  
South America
Argentina, Chile, Ecuador, Peru
  
Brazil, Colombia
  
Deposits in Oceania Continent
  
  
Australia
New Zealand
  
New South Wales, Queensland, Yorke Peninsula
  
All about Obsidian and Jasperoid Properties
Know all about Obsidian and Jasperoid properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian belongs to Igneous Rocks while Jasperoid belongs to Sedimentary Rocks.Texture of Obsidian is Glassy whereas that of Jasperoid is Earthy. Obsidian appears Shiny and Jasperoid appears Glassy or Pearly. The luster of Obsidian is vitreous while that of Jasperoid is vitreous and pearly. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Jasperoid is available in black, brown, colourless, green, grey, pink, white colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Jasperoid are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo).