Definition
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Discoverer
R. J. Hauy
Ferdinand von Hochstetter
Etymology
From Greek pegma, pegmat which means- thing joined together + -ite
From the name of Dun Mountain, New Zealand, + -ite1
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Pegmatitic
Phaneritic
Color
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Rough and Shiny
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, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Types
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Dunite
Features
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Archaeological Significance
Formation
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Mineral Content
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional 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, Sea Erosion, Water Erosion, Wind Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Medium to Coarse Grained
Coarse Grained
Fracture
Conchoidal
Irregular
Porosity
Less Porous
Less Porous
Luster
Grainy, Pearly and Vitreous
Shiny
Specific Gravity
2.6-2.63
3-3.01
Transparency
Translucent to Opaque
Translucent to Opaque
Density
2.6-2.65 g/cm3
2.84-2.85 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
Africa
South Africa
Morocco, South Africa
Europe
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
Deposits in Western Continents
North America
Canada
Canada, USA
South America
Brazil
Argentina, Brazil, Colombia, Ecuador, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New Zealand, Western Australia
All about Pegmatite and Dunite Properties
Know all about Pegmatite and Dunite properties here. All properties of rocks are important as they define the type of rock and its application. Pegmatite and Dunite belong to Igneous Rocks.Texture of Pegmatite is Pegmatitic whereas that of Dunite is Phaneritic. Pegmatite appears Layered, Banded, Veined and Shiny and Dunite appears Rough and Shiny. The luster of Pegmatite is grainy, pearly and vitreous while that of Dunite is shiny. Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors whereas Dunite is available in dark greenish - grey colors. The commercial uses of Pegmatite are creating artwork, jewelry, source of corundum, tourmalines, beryls and topaz and that of Dunite are creating artwork, gemstone, jewelry, source of chromite, platinum, nickel and garnet, source of diamonds.