Definition
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Discoverer
R. J. Hauy
Tornebohm
Etymology
From Greek pegma, pegmat which means- thing joined together + -ite
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Pegmatitic
Earthy, Mud-rich, Rough
Color
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Dull
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Entryways, 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 a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Endoskarns
Features
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
-
Grain Size
Medium to Coarse Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
White
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Grainy, Pearly and Vitreous
Waxy and Dull
Specific Gravity
2.6-2.63
2.86
Transparency
Translucent to Opaque
Opaque
Density
2.6-2.65 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
South Africa
South Africa, Western Africa
Europe
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
United Kingdom
Deposits in Western Continents
North America
Canada
Canada
South America
Brazil
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Central Australia, Western Australia
Pegmatite vs Skarn 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 Skarn characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pegmatite and Properties of Skarn. Learn more about Pegmatite vs Skarn in the next section. The interior uses of Pegmatite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Pegmatite and Skarn, 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 Skarn 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, Gold and silver production, Manufacture of magnesium and dolomite refractories.
More about Pegmatite and Skarn
Here you can know more about Pegmatite and Skarn. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pegmatite and Skarn 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 Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite. You can also check out the list of all Igneous Rocks. When we have to compare Pegmatite vs Skarn, 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, Skarn is available in black, brown, green, grey, white colors. Appearance of Pegmatite is Layered, Banded, Veined and Shiny and that of Skarn is Dull. Properties of rock is another aspect for Pegmatite vs Skarn. The hardness of Pegmatite is 7 and that of Skarn is 6.5. The types of Pegmatite are Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite whereas types of Skarn are Endoskarns. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Pegmatite is white while that of Skarn is light to dark brown. The specific heat capacity of Pegmatite is 0.79 kJ/Kg K and that of Skarn 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 Skarn is heat resistant.