Definition
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Discoverer
R. J. Hauy
Alexandre Brongniart and René Just Haüy
Etymology
From Greek pegma, pegmat which means- thing joined together + -ite
From Greek trakhus rough’ or trakhutēs roughness
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, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Banded
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Flooring, 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 Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, 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
Cemetery Markers, Creating Artwork
Types
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Felsic volcanic rock
Features
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Archaeological Significance
Formation
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. It is the volcanic equivalent of syenite rock and forms as a result of magmatic differentiation.
Mineral Content
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional 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, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Coarse Grained
Fine Grained
Porosity
Less Porous
Less Porous
Luster
Grainy, Pearly and Vitreous
Metallic
Specific Gravity
2.6-2.63
2.7
Transparency
Translucent to Opaque
Opaque
Density
2.6-2.65 g/cm3
2.43-2.45 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
South Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Bulgaria, England, Germany, Norway, Romania, Switzerland
Deposits in Western Continents
South America
Brazil
Brazil, Chile
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New Zealand, Queensland, South Australia, Western Australia
All about Pegmatite and Trachyte Properties
Know all about Pegmatite and Trachyte properties here. All properties of rocks are important as they define the type of rock and its application. Pegmatite and Trachyte belong to Igneous Rocks.Texture of Pegmatite is Pegmatitic whereas that of Trachyte is Aphanitic to Porphyritic. Pegmatite appears Layered, Banded, Veined and Shiny and Trachyte appears Banded. The luster of Pegmatite is grainy, pearly and vitreous while that of Trachyte is metallic. Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors whereas Trachyte is available in black, brown, dark greenish - grey, green, grey, light to dark grey, white colors. The commercial uses of Pegmatite are creating artwork, jewelry, source of corundum, tourmalines, beryls and topaz and that of Trachyte are cemetery markers, creating artwork.