Definition
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Rhomb-porphyry is a porphyritic igneous rock with abundant wedge or lens shaped anorthoclase or feldspar phenocrysts
Discoverer
R. J. Hauy
Unknown
Etymology
From Greek pegma, pegmat which means- thing joined together + -ite
From Latin term that means purple
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Pegmatitic
Aphanitic to Porphyritic
Color
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Rough
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
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
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Metallurgical Flux, Soil Conditioner, Source of Magnesia (MgO)
Types
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Igneous rock
Features
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Host Rock for Lead
Archaeological Significance
Formation
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
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.
Mineral Content
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Alkali feldspar, Biotite, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
CaO, Cl, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Impact 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, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Medium to Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Less Porous
Very Less Porous
Luster
Grainy, Pearly and Vitreous
Subvitreous to Dull
Specific Gravity
2.6-2.63
2.86
Transparency
Translucent to Opaque
Translucent
Density
2.6-2.65 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
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Europe
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Bulgaria
Deposits in Western Continents
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
-
Pegmatite vs Rhomb Porphyry 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. Pegmatite vs Rhomb Porphyry characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pegmatite and Properties of Rhomb Porphyry. Learn more about Pegmatite vs Rhomb Porphyry in the next section. The interior uses of Pegmatite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Rhomb Porphyry include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Pegmatite and Rhomb Porphyry, they have various applications in construction industry. The uses of Pegmatite in construction industry include As dimension stone, Building houses or walls, Construction aggregate, For road aggregate, Landscaping and that of Rhomb Porphyry 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.
More about Pegmatite and Rhomb Porphyry
Here you can know more about Pegmatite and Rhomb Porphyry. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pegmatite and Rhomb Porphyry consists of mineral content and compound content. The mineral content of Pegmatite includes Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz and mineral content of Rhomb Porphyry includes Alkali feldspar, Biotite, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Pegmatite vs Rhomb Porphyry, the texture, color and appearance plays an important role in determining the type of rock. Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors whereas, Rhomb Porphyry is available in black, brown, green, grey, pink, white colors. Appearance of Pegmatite is Layered, Banded, Veined and Shiny and that of Rhomb Porphyry is Rough. Properties of rock is another aspect for Pegmatite vs Rhomb Porphyry. The hardness of Pegmatite is 7 and that of Rhomb Porphyry is 5-5.5. The types of Pegmatite are Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite whereas types of Rhomb Porphyry are Igneous rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Pegmatite and Rhomb Porphyry is white. The specific heat capacity of Pegmatite is 0.79 kJ/Kg K and that of Rhomb Porphyry 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.Pegmatite is heat resistant, impact resistant, pressure resistant whereas Rhomb Porphyry is heat resistant, pressure resistant.