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
Discoverer
Unknown
Obsius
Etymology
From Latin term that means purple
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
Texture
Aphanitic to Porphyritic
Glassy
Color
Black, Brown, Colourless, Green, Grey, Pink, White
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Garden Decoration
Other Architectural Uses
Curbing
Not Yet Used
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
Medical Industry
Not Yet Used
Surgery
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Jewellery
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
Types
Not Available
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Features
Host Rock for Lead
Blocks negativity, Helps to protect against depression
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
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.
Mineral Content
Alkali feldspar, Biotite, Plagioclase, Pyroxene
Not Available
Compound Content
CaO, Cl, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Fine Grained
Not Applicable
Fracture
Conchoidal
Conchoidal
Porosity
Very Less Porous
Very Less Porous
Luster
Subvitreous to Dull
Vitreous
Cleavage
Perfect
Non-Existent
Toughness
2.7
Not Available
Specific Gravity
2.86
2.6-2.7
Transparency
Translucent
Translucent
Density
2.8-2.9 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
Afghanistan, Indonesia, Japan, Russia
Africa
Not Yet Found
Kenya
Europe
Bulgaria
Greece, Hungary, Iceland, Italy, Turkey
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Not Yet Found
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
Not Yet Found
New Zealand
Rhomb Porphyry vs Obsidian Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Rhomb Porphyry vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rhomb Porphyry and Properties of Obsidian. Learn more about Rhomb Porphyry vs Obsidian in the next section. The interior uses of Rhomb Porphyry include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Rhomb Porphyry and Obsidian, they have various applications in construction industry. The uses of Rhomb Porphyry in construction industry include 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 and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Rhomb Porphyry and Obsidian
Here you can know more about Rhomb Porphyry and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rhomb Porphyry and Obsidian consists of mineral content and compound content. The mineral content of Rhomb Porphyry includes Alkali feldspar, Biotite, Plagioclase, Pyroxene and mineral content of Obsidian is not available. You can also check out the list of all Igneous Rocks. When we have to compare Rhomb Porphyry vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Rhomb Porphyry is available in black, brown, colourless, green, grey, pink, white colors whereas, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Rhomb Porphyry is Rough and that of Obsidian is Shiny. Properties of rock is another aspect for Rhomb Porphyry vs Obsidian. Hardness of Rhomb Porphyry and Obsidian is 5-5.5. The types of Rhomb Porphyry are Not Available whereas types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Rhomb Porphyry and Obsidian is white. The specific heat capacity of Rhomb Porphyry is 0.92 kJ/Kg K and that of Obsidian is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Rhomb Porphyry is heat resistant, pressure resistant whereas Obsidian is heat resistant, impact resistant.