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
Jasperoid is a rare, peculiar type of metasomatic alteration of rocks
Discoverer
Unknown
Unknown
Etymology
From German which means hornstone
From silica, the main mineral content of Jasperoid
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular, Platy
Earthy
Color
Brown, Dark Greenish - Grey, Green, Reddish Brown
Black, Brown, Colourless, Green, Grey, Pink, White
Durability
Durable
Durable
Appearance
Dull
Glassy or Pearly
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
for Road Aggregate, Roadstone
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics, Serves as an Oil and Gas Reservoir rock
Medical Industry
Not Yet Used
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Monuments
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Biotite hornfels
Not Available
Features
Smooth to touch
Host Rock for Lead, Traps for subsurface fluids like Oil and Natural Gas., Zinc and Copper Deposits
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Figurines
Not Yet Used
Used
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.
Jasperoid is a rare and peculiar type of metasomatic alteration of rocks. It is formed by extreme alteration of wall rocks within a shear zone which may occur in sediments, andesites, trachytes and basalts.
Mineral Content
Andalusite
Clay Minerals, Pyrite, Quartz, Sulfides
Compound Content
Fe, Mg
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Not Applicable
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Less Porous
Luster
Shiny
Vitreous and Pearly
Toughness
Not Yet Found
1
Specific Gravity
3.4-3.9
2.8-3
Transparency
Opaque
Transparent to Translucent
Density
0.25-0.30 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
China, India
Africa
Cameroon, East Africa, Tanzania, Western Africa
Morocco, Namibia
Europe
United Kingdom
Austria, Italy, Romania, Spain, Switzerland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Mexico, USA
South America
Bolivia, Brazil, Colombia, Ecuador
Brazil, Colombia
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Western Australia
New South Wales, Queensland, Yorke Peninsula
All about Hornfels and Jasperoid Properties
Know all about Hornfels and Jasperoid properties here. All properties of rocks are important as they define the type of rock and its application. Hornfels belongs to Metamorphic Rocks while Jasperoid belongs to Sedimentary Rocks.Texture of Hornfels is Granular, Platy whereas that of Jasperoid is Earthy. Hornfels appears Dull and Jasperoid appears Glassy or Pearly. The luster of Hornfels is shiny while that of Jasperoid is vitreous and pearly. Hornfels is available in brown, dark greenish - grey, green, reddish brown colors whereas Jasperoid is available in black, brown, colourless, green, grey, pink, white colors. The commercial uses of Hornfels are cemetery markers, commemorative tablets, creating artwork and that of Jasperoid are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo).