Definition
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock
Discoverer
Unknown
Unknown
Etymology
From a Latin word tophous then in Italian tufo and finally tuff
From German which means hornstone
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Group
Volcanic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Pyroclastic
Granular, Platy
Color
Brown, Grey, Yellow
Brown, Dark Greenish - Grey, Green, Reddish Brown
Durability
Durable
Durable
Appearance
Dull, Vesicular and Foilated
Dull
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Construction Aggregate
for Road Aggregate, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.
Biotite hornfels
Features
Always found as volcanic pipes over deep continental crust
Smooth to touch
Archaeological Significance
Famous Monuments
Easter Island in the Polynesian Triangle, Pacific Ocean
Data Not Available
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Calcite, Chlorite
Andalusite
Compound Content
Hydrogen Sulfide, Sulfur Dioxide
Fe, Mg
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Uneven
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Vitreous to Dull
Shiny
Cleavage
Not Available
Perfect
Toughness
Not Available
Not Yet Found
Specific Gravity
2.73
3.4-3.9
Transparency
Opaque
Opaque
Density
1-1.8 g/cm3
0.25-0.30 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
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
Africa
Cameroon, Cape Verde, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Uganda
Cameroon, East Africa, Tanzania, Western Africa
Europe
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
United Kingdom
Others
Antarctica, Hawaii Islands
Not Yet Found
Deposits in Western Continents
North America
Canada, Costa Rica, Panama, USA
Canada, USA
South America
Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay
Bolivia, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, New Zealand, Queensland, Western Australia
Tuff vs Hornfels 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 Hornfels characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Tuff and Properties of Hornfels. Learn more about Tuff vs Hornfels in the next section. The interior uses of Tuff include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Tuff and Hornfels, they have various applications in construction industry. The uses of Tuff in construction industry include Building houses or walls, Construction aggregate and that of Hornfels include For road aggregate, Roadstone.
More about Tuff and Hornfels
Here you can know more about Tuff and Hornfels. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Tuff and Hornfels consists of mineral content and compound content. The mineral content of Tuff includes Calcite, Chlorite and mineral content of Hornfels includes Andalusite. You can also check out the list of all Igneous Rocks. When we have to compare Tuff vs Hornfels, the texture, color and appearance plays an important role in determining the type of rock. Tuff is available in brown, grey, yellow colors whereas, Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. Appearance of Tuff is Dull, Vesicular and Foilated and that of Hornfels is Dull. Properties of rock is another aspect for Tuff vs Hornfels. The hardness of Tuff is 4-6 and that of Hornfels is 2-3. The types of Tuff are Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite. whereas types of Hornfels are Biotite hornfels. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Tuff is white while that of Hornfels is unknown. The specific heat capacity of Tuff is 0.20 kJ/Kg K and that of Hornfels is 0.84 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 Hornfels is heat resistant, impact resistant, pressure resistant.