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
  
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
  
History
  
  
Origin
New Zealand
  
Indonesia
  
Discoverer
Unknown
  
Cornish Gossen
  
Etymology
From German which means hornstone
  
From Cornish gossen from gos, blood from Old Cornish guit
  
Class
Metamorphic Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Soft Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Granular, Platy
  
Rough, Sandy
  
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
  
Brown, Brown- Black, Gold, Green, Rust
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull
  
Dull and Banded
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
  
Countertops, Decorative Aggregates, 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
  
Industry
  
  
Construction Industry
for Road Aggregate, Roadstone
  
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Cemetery Markers, Commemorative Tablets, Gemstone
  
Types
Biotite hornfels
  
Translocated gossan and Leakage gossan
  
Features
Smooth to touch
  
Clasts are smooth to touch, Easily splits into thin plates
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Not Applicable
  
Sculpture
Not Yet Used
  
Not Yet Used
  
Famous Sculptures
Not Applicable
  
Not Applicable
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
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.
  
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
  
Composition
  
  
Mineral Content
Andalusite
  
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
  
Compound Content
Fe, Mg
  
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
  
Transformation
  
  
Metamorphism
No
  
No
  
Types of Metamorphism
Not Applicable
  
Not Applicable
  
Weathering
Yes
  
No
  
Types of Weathering
Biological Weathering
  
Not Applicable
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Chemical Erosion, Sea Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
2-3
  
4-5
  
Grain Size
Fine Grained
  
Fine to Medium Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
Unknown
  
White to Grey
  
Porosity
Highly Porous
  
Highly Porous
  
Luster
Shiny
  
Metallic
  
Compressive Strength
Not Available
  
Cleavage
Perfect
  
Not Available
  
Toughness
Not Yet Found
  
Not Available
  
Specific Gravity
3.4-3.9
  
2.0
  
Transparency
Opaque
  
Opaque
  
Density
0.25-0.30 g/cm3
  
Not Available
  
Thermal Properties
  
  
Specific Heat Capacity
0.84 kJ/Kg K
  
15
0.24 kJ/Kg K
  
24
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant
  
Deposits in Eastern Continents
  
  
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
  
China, India, Indonesia, Russia, Singapore, South Korea
  
Africa
Cameroon, East Africa, Tanzania, Western Africa
  
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
  
Europe
United Kingdom
  
Albania, France, Germany, Great Britain, United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, USA
  
South America
Bolivia, Brazil, Colombia, Ecuador
  
Brazil, Colombia, Ecuador
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, New Zealand, Queensland, Western Australia
  
New South Wales, South Australia, Western Australia
  
Hornfels vs Gossan 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 Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Hornfels and Properties of Gossan. Learn more about Hornfels vs Gossan in the next section. The interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Hornfels and Gossan, they have various applications in construction industry. The uses of Hornfels in construction industry include For road aggregate, Roadstone and that of Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Hornfels and Gossan
Here you can know more about Hornfels and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Hornfels and Gossan consists of mineral content and compound content. The mineral content of Hornfels includes Andalusite and mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon. You can also check out the list of all Metamorphic Rocks. When we have to compare Hornfels vs Gossan, 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, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Hornfels is Dull and that of Gossan is Dull and Banded. Properties of rock is another aspect for Hornfels vs Gossan. The hardness of Hornfels is 2-3 and that of Gossan is 4-5. The types of Hornfels are Biotite hornfels whereas types of Gossan are Translocated gossan and Leakage gossan. 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 Gossan is white to grey. The specific heat capacity of Hornfels is 0.84 kJ/Kg K and that of Gossan is 0.24 kJ/Kg K. 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 Gossan is heat resistant, impact resistant, pressure resistant.