1 Definition
1.1 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
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From German which means hornstone
From the Middle High German verb gneist (to spark; so called because the rock glitters)
1.4 Class
Metamorphic Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
Not Applicable
Not Applicable
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Granular, Platy
Banded, Foliated, Platy
2.2 Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Black, Brown, Pink, Red, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
for Road Aggregate, Roadstone
As Dimension Stone
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments
Artifacts
3.4 Other Uses
3.4.1 Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
4 Types
4.1 Types
Biotite hornfels
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
4.2 Features
Smooth to touch
Generally rough to touch, Is one of the oldest rock
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Konark Sun Temple in India, Washington Monument, US
4.3.3 Sculpture
Not Yet Used
Not Yet Used
4.3.4 Famous Sculptures
Not Applicable
Not Applicable
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
Not Yet Used
Not Yet Used
4.4 Fossils
5 Formation
5.1 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.
Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.
5.2 Composition
5.2.1 Mineral Content
Andalusite
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
5.2.2 Compound Content
Fe, Mg
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Not Applicable
Impact Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering
Biological Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine Grained
Medium to Coarse Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Very Less Porous
6.1.6 Luster
6.1.7 Compressive Strength
5.80 N/mm2125.00 N/mm2
0.15
450
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
Opaque
Translucent to Opaque
6.1.12 Density
0.25-0.30 g/cm32.6-2.9 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
7.1.2 Africa
Cameroon, East Africa, Tanzania, Western Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
7.1.3 Europe
United Kingdom
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
7.2.2 South America
Bolivia, Brazil, Colombia, Ecuador
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
7.3 Deposits in Oceania Continent
7.3.1 Australia
New South Wales, New Zealand, Queensland, Western Australia
New South Wales, New Zealand, Queensland, Victoria