Definition
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
Breccia is a rock consisting of angular fragments of stones which are cemented by finer calcareous material
Origin
New Zealand
England
Discoverer
Unknown
Unknown
Etymology
From German which means hornstone
From Italian, literally gravel, Germanic origin and related to break
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular, Platy
Brecciated, Clastic
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Beige, Black, Blue, Brown, Buff, Green, Grey, Orange, Pink, Purple, Red, Rust, White, Yellow
Durability
Durable
Durable
Appearance
Dull
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
for Road Aggregate, Roadstone
As Dimension Stone, Construction Aggregate, Landscaping, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments
Artifacts, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Creating Artwork, Gemstone, Jewelry
Types
Biotite hornfels
Collapse Breccia, Fault Breccia, Flow Breccia, Pyroclastic Breccia, Igneous Breccia and Impact Breccia
Features
Smooth to touch
Available in Lots of Colors and Patterns, Clasts are smooth to touch
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Not Yet Used
Used
Formation
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.
Breccia is a clastic sedimentary rock which is composed of broken fragments of minerals or rock which are cemented together by a fine-grained matrix and it forms where broken, angular fragments of rock or mineral debris accumulate.
Mineral Content
Andalusite
Calcite, Clay, Feldspar, Phosphates, Quartz, Silica
Compound Content
Fe, Mg
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, Potassium Oxide, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion
Grain Size
Fine Grained
Medium to Coarse Grained
Fracture
Conchoidal
Uneven
Porosity
Highly Porous
Less Porous
Luster
Shiny
Dull to Pearly
Compressive Strength
Not Available
Cleavage
Perfect
Non-Existent
Toughness
Not Yet Found
Not Available
Specific Gravity
3.4-3.9
2.86-2.87
Transparency
Opaque
Opaque
Density
0.25-0.30 g/cm3
0 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
China, India, Kazakhstan, Mongolia, Russia, South Korea, Uzbekistan
Africa
Cameroon, East Africa, Tanzania, Western Africa
Namibia, Nigeria, South Africa
Europe
United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
Canada, USA
Barbados, Canada, Mexico, Panama, USA
South America
Bolivia, Brazil, Colombia, Ecuador
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Western Australia
New South Wales, New Zealand
Hornfels vs Breccia 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. Hornfels vs Breccia characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Hornfels and Properties of Breccia. Learn more about Hornfels vs Breccia in the next section. The interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Breccia include Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels and Interior decoration. Due to some exceptional properties of Hornfels and Breccia, they have various applications in construction industry. The uses of Hornfels in construction industry include For road aggregate, Roadstone and that of Breccia include As dimension stone, Construction aggregate, Landscaping, Roadstone.
More about Hornfels and Breccia
Here you can know more about Hornfels and Breccia. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Hornfels and Breccia consists of mineral content and compound content. The mineral content of Hornfels includes Andalusite and mineral content of Breccia includes Calcite, Clay, Feldspar, Phosphates, Quartz, Silica. You can also check out the list of all Metamorphic Rocks. When we have to compare Hornfels vs Breccia, the texture, color and appearance plays an important role in determining the type of rock. Hornfels is available in brown, dark greenish - grey, green, reddish brown colors whereas, Breccia is available in beige, black, blue, brown, buff, green, grey, orange, pink, purple, red, rust, white, yellow colors. Appearance of Hornfels is Dull and that of Breccia is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Hornfels vs Breccia. The hardness of Hornfels is 2-3 and that of Breccia is 7. The types of Hornfels are Biotite hornfels whereas types of Breccia are Collapse Breccia, Fault Breccia, Flow Breccia, Pyroclastic Breccia, Igneous Breccia and Impact Breccia. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Hornfels is unknown while that of Breccia is white. The specific heat capacity of Hornfels is 0.84 kJ/Kg K and that of Breccia is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Hornfels is heat resistant, impact resistant, pressure resistant whereas Breccia is heat resistant, impact resistant, pressure resistant, wear resistant.
