Definition
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Discoverer
R. J. Hauy
Unknown
Etymology
From Greek pegma, pegmat which means- thing joined together + -ite
From Greek mulōn mill + -ite
Class
Igneous Rocks
Metamorphic 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
Foliated
Color
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Black to Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Dull, Banded and Foilated
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
for Road Aggregate, Landscaping, Roadstone
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Creating Artwork, Gemstone, Jewelry
Types
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Blastomylonites, Ultramylonites and Phyllonites
Features
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Surfaces are often shiny
Archaeological Significance
Formation
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Mineral Content
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Porphyroblasts
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
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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, Sea Erosion, Wind Erosion
Grain Size
Medium to Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Grainy, Pearly and Vitreous
Shiny
Cleavage
Perfect
Conchoidal
Specific Gravity
2.6-2.63
2.97-3.05
Transparency
Translucent to Opaque
Opaque
Density
2.6-2.65 g/cm3
2.6-4.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
China, India, Indonesia, Saudi Arabia, South Korea
Africa
South Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Europe
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Deposits in Western Continents
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Central Australia, Western Australia
All about Pegmatite and Mylonite Properties
Know all about Pegmatite and Mylonite properties here. All properties of rocks are important as they define the type of rock and its application. Pegmatite belongs to Igneous Rocks while Mylonite belongs to Metamorphic Rocks.Texture of Pegmatite is Pegmatitic whereas that of Mylonite is Foliated. Pegmatite appears Layered, Banded, Veined and Shiny and Mylonite appears Dull, Banded and Foilated. The luster of Pegmatite is grainy, pearly and vitreous while that of Mylonite is shiny. Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors whereas Mylonite is available in black to grey colors. The commercial uses of Pegmatite are creating artwork, jewelry, source of corundum, tourmalines, beryls and topaz and that of Mylonite are creating artwork, gemstone, jewelry.