1 Definition
1.1 Definition
Rhomb-porphyry is a porphyritic igneous rock with abundant wedge or lens shaped anorthoclase or feldspar phenocrysts
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
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Latin term that means purple
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
1.4 Class
Igneous Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
2 Texture
2.1 Texture
Aphanitic to Porphyritic
Glassy
2.2 Color
Black, Brown, Colourless, Green, Grey, Pink, White
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
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, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Garden Decoration
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
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
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
3.2.2 Medical Industry
3.3 Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Jewellery
3.4 Other Uses
3.4.1 Commercial Uses
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Metallurgical Flux, Soil Conditioner, Source of Magnesia (MgO)
Creating Artwork, Mirror, Used in aquariums
4 Types
4.1 Types
Not Available
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
4.2 Features
Host Rock for Lead
Blocks negativity, Helps to protect against depression
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Not Applicable
4.3.3 Sculpture
4.3.4 Famous Sculptures
Data Not Available
Not Applicable
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 Formation
Rhomb-porphyry 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.
5.2 Composition
5.2.1 Mineral Content
Alkali feldspar, Biotite, Plagioclase, Pyroxene
Not Available
5.2.2 Compound Content
CaO, Cl, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
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, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine Grained
Not Applicable
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Very Less Porous
Very Less Porous
6.1.6 Luster
Subvitreous to Dull
Vitreous
6.1.7 Compressive Strength
310.00 N/mm20.15 N/mm2
0.15
450
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
2.8-2.9 g/cm32.6 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
0.92 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
6.2.2 Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Not Yet Found
Afghanistan, Indonesia, Japan, Russia
7.1.2 Africa
7.1.3 Europe
Bulgaria
Greece, Hungary, Iceland, Italy, Turkey
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Not Yet Found
Argentina, Chile, Ecuador, Peru
7.3 Deposits in Oceania Continent
7.3.1 Australia
Not Yet Found
New Zealand