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
Litchfieldite is a rare igneous rock which is coarse-grained, foliated and a variety of nepheline syenite, sometimes also called as nepheline syenite gneiss or gneissic nepeheline syenite
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From its occurrence at Litchfield, Maine, USA
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Opaque Rock
Coarse Grained Rock, Opaque Rock
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Brown, Buff, Cream, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Banded and Foilated
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics
Medical Industry
Surgery
-
Antiquity Uses
Artifacts, Jewellery
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
Creating Artwork
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Borolanite and Litchfieldite
Features
Blocks negativity, Helps to protect against depression
Application of acids on the surface causes cloudy frosting, Available in Lots of Colors and Patterns, Dissolves in hydrochloric acid, Is one of the oldest rock
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.
Litchfieldite 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.
Mineral Content
-
Albite, Amphibole, Biotite, Cancrinite, Feldspar, Hornblende, Plagioclase, Pyroxene, Sodalite
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
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
-
Coarse Grained
Fracture
Conchoidal
Conchoidal to Uneven
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Greasy to Dull
Specific Gravity
2.6-2.7
2.6
Transparency
Translucent
Translucent to Opaque
Density
2.6 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
-
Africa
Kenya
South Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Finland, Norway, Portugal
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada
South America
Argentina, Chile, Ecuador, Peru
Brazil
Deposits in Oceania Continent
All about Obsidian and Litchfieldite Properties
Know all about Obsidian and Litchfieldite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian and Litchfieldite belong to Igneous Rocks.Texture of Obsidian is Glassy whereas that of Litchfieldite is Granular. Obsidian appears Shiny and Litchfieldite appears Banded and Foilated. The luster of Obsidian is vitreous while that of Litchfieldite is greasy to dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Litchfieldite is available in brown, buff, cream, green, grey, pink, white colors. The commercial uses of Obsidian and Litchfieldite are creating artwork, mirror, used in aquariums.