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
  
Claystone is a fine-grained, dark gray to pink sedimentary rock which mainly consists of compacted and hardened clay
  
History
  
  
Origin
New Zealand
  
Unknown
  
Discoverer
Unknown
  
Unknown
  
Etymology
From German which means hornstone
  
From English clay and stone as the rock contains more amount of clay
  
Class
Metamorphic Rocks
  
Sedimentary 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, Opaque Rock
  
Texture
Granular, Platy
  
Clastic
  
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
  
Black, Blue, Brown, Green, Grey, Orange, Red, White, Yellow
  
Maintenance
Less
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull
  
Rough and Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
  
Decorative Aggregates, Entryways, Floor Tiles, Homes, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
As Facing Stone, Roof Tiles
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
for Road Aggregate, Roadstone
  
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Pottery
  
Types
Biotite hornfels
  
Not Available
  
Features
Smooth to touch
  
Available in Lots of Colors and Patterns, Smooth to touch, Very fine grained rock
  
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
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Present
  
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.
  
Claystone is generally quite soft, but can be hard and brittle. It forms due to weathering of mudstone.
  
Composition
  
  
Mineral Content
Andalusite
  
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
  
Compound Content
Fe, Mg
  
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, MgO, Silicon Dioxide
  
Transformation
  
  
Metamorphism
No
  
No
  
Types of Metamorphism
Not Applicable
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Coastal Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
2-3
  
3.5-4
  
Grain Size
Fine Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Not Available
  
Streak
Unknown
  
White
  
Porosity
Highly Porous
  
Very Less Porous
  
Luster
Shiny
  
Dull
  
Compressive Strength
Not Available
  
Cleavage
Perfect
  
Perfect
  
Toughness
Not Yet Found
  
2.6
  
Specific Gravity
3.4-3.9
  
0
  
Transparency
Opaque
  
Opaque
  
Density
0.25-0.30 g/cm3
  
2-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.84 kJ/Kg K
  
15
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
  
Bangladesh, China, India, Russia
  
Africa
Cameroon, East Africa, Tanzania, Western Africa
  
Ethiopia, Kenya, Morocco, South Africa, Tanzania
  
Europe
United Kingdom
  
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, Panama, USA
  
South America
Bolivia, Brazil, Colombia, Ecuador
  
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, New Zealand, Queensland, Western Australia
  
New South Wales, New Zealand, Queensland, Victoria, Western Australia
  
Hornfels vs Claystone 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 Claystone characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Hornfels and Properties of Claystone. Learn more about Hornfels vs Claystone in the next section. The interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Claystone include Decorative aggregates, Entryways, Floor tiles, Homes and Interior decoration. Due to some exceptional properties of Hornfels and Claystone, they have various applications in construction industry. The uses of Hornfels in construction industry include For road aggregate, Roadstone and that of Claystone include As a sintering agent in steel industry to process iron ore, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Hornfels and Claystone
Here you can know more about Hornfels and Claystone. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Hornfels and Claystone consists of mineral content and compound content. The mineral content of Hornfels includes Andalusite and mineral content of Claystone includes Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz. You can also check out the list of all Metamorphic Rocks. When we have to compare Hornfels vs Claystone, 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, Claystone is available in black, blue, brown, green, grey, orange, red, white, yellow colors. Appearance of Hornfels is Dull and that of Claystone is Rough and Dull. Properties of rock is another aspect for Hornfels vs Claystone. The hardness of Hornfels is 2-3 and that of Claystone is 3.5-4. The types of Hornfels are Biotite hornfels whereas types of Claystone are Not Available. 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 Claystone is white. The specific heat capacity of Hornfels is 0.84 kJ/Kg K and that of Claystone is 0.92 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 Claystone is heat resistant, impact resistant.