1 Definition
1.1 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
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
1.2 History
1.2.1 Origin
1.2.2 Discoverer
Obsius
Alexandre Brongniart
1.3 Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Opaque Rock
Coarse Grained Rock, Opaque Rock
2 Texture
2.1 Texture
2.2 Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Reddish Brown
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
3.1.2 Exterior Uses
Garden Decoration
Paving Stone, Office Buildings
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
3.2.2 Medical Industry
3.3 Antiquity Uses
Artifacts, Jewellery
Artifacts, Sculpture, Small Figurines
3.4 Other Uses
3.4.1 Commercial Uses
Creating Artwork, Mirror, Used in aquariums
In aquifers, Soil Conditioner, Source of Magnesia (MgO), Tombstones
4 Types
4.1 Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Not Available
4.2 Features
Blocks negativity, Helps to protect against depression
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
4.3 Archaeological Significance
4.3.1 Monuments
Not Yet Used
Not Yet Used
4.3.2 Famous Monuments
Not Applicable
Not Applicable
4.3.3 Sculpture
4.3.4 Famous Sculptures
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
Arkose rock forms from the weathering of feldspar-rich igneous or metamorphic rock, most commonly granitic rocks, which are primarily composed of quartz and feldspar.
5.2 Composition
5.2.1 Mineral Content
Not Available
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
5.2.2 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, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Not Applicable
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Not Applicable
Coarse Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Very Less Porous
Highly Porous
6.1.6 Luster
6.1.7 Compressive Strength
6.1.8 Cleavage
Non-Existent
Not Available
6.1.9 Toughness
Not Available
Not Available
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
2.6 g/cm3Not Available
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
7.1.2 Africa
Kenya
Namibia, Nigeria, South Africa
7.1.3 Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
7.1.4 Others
7.2 Deposits in Western Continents
7.2.1 North America
Canada, Mexico, USA
Canada, USA
7.2.2 South America
Argentina, Chile, Ecuador, Peru
Brazil
7.3 Deposits in Oceania Continent
7.3.1 Australia
New Zealand
New South Wales, New Zealand