Definition
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
History
Origin
New Zealand
Discoverer
Unknown
Etymology
From German which means hornstone
Class
Metamorphic Rocks
Sub-Class
Durable Rock, Soft Rock
Family
Group
-
Other Categories
Fine Grained Rock, Opaque Rock
Texture
Texture
Granular, Platy
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Maintenance
Less
Durability
Durable
Water Resistant
✔
✘
81% - Metamorphic Rocks Rocks have it !
Scratch Resistant
✔
✘
65% - Metamorphic Rocks Rocks
Stain Resistant
✔
✘
42% - Metamorphic Rocks Rocks
Wind Resistant
✔
✘
19% - Metamorphic Rocks Rocks
Acid Resistant
✔
✘
15% - Metamorphic Rocks Rocks
Appearance
Dull
Uses
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Industry
Construction Industry
for Road Aggregate, Roadstone
Medical Industry
-
Antiquity Uses
Artifacts, Monuments
Other Uses
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Types
Biotite hornfels
Features
Smooth to touch
Archaeological Significance
Monuments
-
Famous Monuments
-
Sculpture
-
Famous Sculptures
-
Pictographs
-
Petroglyphs
-
Figurines
-
Fossils
Absent
Formation
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.
Composition
Mineral Content
Andalusite
Compound Content
Fe, Mg
Transformation
Metamorphism
✔
✘
50% - Metamorphic Rocks Rocks
Types of Metamorphism
-
Weathering
✔
✘
65% - Metamorphic Rocks Rocks have it !
Types of Weathering
Biological Weathering
Erosion
✔
✘
77% - Metamorphic Rocks Rocks have it !
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Properties
Physical Properties
Hardness
2-3
1
7
👆🏻
Grain Size
Fine Grained
Fracture
Conchoidal
Streak
-
Porosity
Highly Porous
Luster
Shiny
Compressive Strength
5.80 N/mm2
Rank: 46 (Overall)
0.15
450
👆🏻
Cleavage
Perfect
Toughness
-
Specific Gravity
3.4-3.9
0
8.4
👆🏻
Transparency
Opaque
Density
0.25-0.30 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.84 kJ/Kg K
Rank: 15 (Overall)
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Reserves
Deposits in Eastern Continents
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
Africa
Cameroon, East Africa, Tanzania, Western Africa
Europe
United Kingdom
Others
-
Deposits in Western Continents
North America
Canada, USA
South America
Bolivia, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Western Australia