Definition
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Discoverer
Unknown
R. J. Hauy
Etymology
From a Latin word tophous then in Italian tufo and finally tuff
From Greek pegma, pegmat which means- thing joined together + -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Clastic, Pyroclastic
Pegmatitic
Color
Brown, Grey, Yellow
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Vesicular and Foilated
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Construction Aggregate
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture, Small Figurines
Commercial Uses
Creating Artwork
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Types
Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Features
Always found as volcanic pipes over deep continental crust
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Archaeological Significance
Famous Monuments
Easter Island in the Polynesian Triangle, Pacific Ocean
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Formation
Tuff is formed when large masses of ash and sand which are mixed with hot gases are ejected by a volcano and avalanche rapidly down its slopes.
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Mineral Content
Calcite, Chlorite
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Compound Content
Hydrogen Sulfide, Sulfur Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
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
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
Fine Grained
Medium to Coarse Grained
Fracture
Uneven
Conchoidal
Porosity
Highly Porous
Less Porous
Luster
Vitreous to Dull
Grainy, Pearly and Vitreous
Specific Gravity
2.73
2.6-2.63
Transparency
Opaque
Translucent to Opaque
Density
1-1.8 g/cm3
2.6-2.65 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Armenia, Azerbaijan, Burma, Cambodia, China, India, Indonesia, Iran, Japan, Malaysia, Mongolia, Nepal, North Korea, Pakistan, Saudi Arabia, Syria, Taiwan, Thailand, Turkey, Vietnam, Yemen
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
Africa
Cameroon, Cape Verde, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Uganda
South Africa
Europe
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Others
Antarctica, Hawaii Islands
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Deposits in Western Continents
North America
Canada, Costa Rica, Panama, USA
Canada
South America
Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay
Brazil
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Tuff vs Pegmatite 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. Tuff vs Pegmatite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Tuff and Properties of Pegmatite. Learn more about Tuff vs Pegmatite in the next section. The interior uses of Tuff include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Pegmatite include Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Tuff and Pegmatite, they have various applications in construction industry. The uses of Tuff in construction industry include Building houses or walls, Construction aggregate and that of Pegmatite include As dimension stone, Building houses or walls, Construction aggregate, For road aggregate, Landscaping.
More about Tuff and Pegmatite
Here you can know more about Tuff and Pegmatite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Tuff and Pegmatite consists of mineral content and compound content. The mineral content of Tuff includes Calcite, Chlorite and mineral content of Pegmatite includes Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz. You can also check out the list of all Igneous Rocks. When we have to compare Tuff vs Pegmatite, the texture, color and appearance plays an important role in determining the type of rock. Tuff is available in brown, grey, yellow colors whereas, Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors. Appearance of Tuff is Dull, Vesicular and Foilated and that of Pegmatite is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Tuff vs Pegmatite. The hardness of Tuff is 4-6 and that of Pegmatite is 7. The types of Tuff are Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite. whereas types of Pegmatite are Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Tuff and Pegmatite is white. The specific heat capacity of Tuff is 0.20 kJ/Kg K and that of Pegmatite is 0.79 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Tuff is heat resistant, impact resistant, pressure resistant, wear resistant whereas Pegmatite is heat resistant, impact resistant, pressure resistant.