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
A hydration and metamorphic transformation of ultramafic rock from the Earth's mantle is called as serpentinization, a group of minerals is formed by serpentinization compose rock 'serpentinite'.
Discoverer
Obsius
Unknown
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From English word serpentinization.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Shiny
Rough and Dull
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Medical Industry
Surgery
-
Antiquity Uses
Artifacts, Jewellery
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
Commemorative Tablets, Creating Artwork
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Jadeitite
Features
Blocks negativity, Helps to protect against depression
Host Rock for Lead
Archaeological Significance
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Serpentinite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
-
Carbonate, Magnetite, Pyrrhotite, Serpentine, Sulfides
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, CaO, Carbon Dioxide, KCl, MgO, Sulfur Dioxide, Sulphur
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Wind Erosion
Grain Size
-
Very fine-grained
Fracture
Conchoidal
Uneven
Streak
White
White, Greenish White or Grey
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Waxy and Dull
Specific Gravity
2.6-2.7
2.79-3
Transparency
Translucent
Opaque
Density
2.6 g/cm3
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
India, Saudi Arabia, Singapore, South Korea
Africa
Kenya
Ethiopia, Western Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
England, Georgia, Switzerland, United Kingdom
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada
South America
Argentina, Chile, Ecuador, Peru
Colombia
Deposits in Oceania Continent
Australia
New Zealand
Central Australia, New South Wales, New Zealand, Western Australia
All about Obsidian and Serpentinite Properties
Know all about Obsidian and Serpentinite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian belongs to Igneous Rocks while Serpentinite belongs to Metamorphic Rocks.Texture of Obsidian is Glassy whereas that of Serpentinite is Earthy. Obsidian appears Shiny and Serpentinite appears Rough and Dull. The luster of Obsidian is vitreous while that of Serpentinite is waxy and dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Serpentinite is available in black, brown, green, grey, white colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Serpentinite are commemorative tablets, creating artwork.