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
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From German which means hornstone
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
1.4 Class
Metamorphic Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
Not Applicable
Not Applicable
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Granular, Platy
Clastic, Splintery
2.2 Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Black, Brown, Buff, Green, Grey, Red, Yellow
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
Decorative Aggregates, Homes, 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, Office Buildings
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
for Road Aggregate, Roadstone
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments
Artifacts, Sculpture
3.4 Other Uses
3.4.1 Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Creating Artwork, Pottery
4 Types
4.1 Types
Biotite hornfels
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
4.2 Features
Smooth to touch
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Jantar Mantar in India
4.3.3 Sculpture
4.3.4 Famous Sculptures
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
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.
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
5.2 Composition
5.2.1 Mineral Content
Andalusite
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
5.2.2 Compound Content
Fe, Mg
Ca, Fe, Mg, Silicon Dioxide, Sodium
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Not Applicable
Not Applicable
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering
Biological Weathering, Chemical 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, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine Grained
Very fine-grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Highly Porous
6.1.6 Luster
6.1.7 Compressive Strength
5.80 N/mm295.00 N/mm2
0.15
450
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
0.25-0.30 g/cm32.4-2.8 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
0.84 kJ/Kg K0.39 kJ/Kg K
0.14
3.2
6.2.2 Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact 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
Bangladesh, China, India, Russia
7.1.2 Africa
Cameroon, East Africa, Tanzania, Western Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
7.1.3 Europe
United Kingdom
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Bolivia, Brazil, Colombia, Ecuador
Bolivia, 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, Western Australia