Definition
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
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
Origin
Hawaii Islands
New Zealand
Discoverer
Unknown
Unknown
Etymology
From Greek pikros bitter + -ite, 19th century
From German which means hornstone
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Group
Volcanic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Earthy, Rough
Granular, Platy
Color
Black, Brown, Colourless, Green, Grey, Pink, White, Yellow
Brown, Dark Greenish - Grey, Green, Reddish Brown
Durability
Durable
Durable
Appearance
Rough and Shiny
Dull
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, for Road Aggregate, Manufacture of Magnesium and Dolomite Refractories, Roadstone, Used for flooring, stair treads, borders and window sills.
for Road Aggregate, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments
Commercial Uses
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Oceanite
Biotite hornfels
Features
Host Rock for Lead
Smooth to touch
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Used
Not Yet Used
Formation
Picrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
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.
Mineral Content
Biotite, Olivine, Plagioclase, Pyrrhotite
Andalusite
Compound Content
Al, CaO, Carbon Dioxide, Mg, MgO
Fe, Mg
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Uneven
Conchoidal
Streak
White, Greenish White or Grey
Unknown
Porosity
Less Porous
Highly Porous
Luster
Subvitreous to Dull
Shiny
Cleavage
Imperfect
Perfect
Toughness
2.1
Not Yet Found
Specific Gravity
2.75-2.92
3.4-3.9
Transparency
Opaque
Opaque
Density
1.5-2.5 g/cm3
0.25-0.30 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
India, Russia
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
Africa
South Africa
Cameroon, East Africa, Tanzania, Western Africa
Europe
Iceland
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Bolivia, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Not Yet Found
New South Wales, New Zealand, Queensland, Western Australia
All about Picrite and Hornfels Properties
Know all about Picrite and Hornfels properties here. All properties of rocks are important as they define the type of rock and its application. Picrite belongs to Igneous Rocks while Hornfels belongs to Metamorphic Rocks.Texture of Picrite is Earthy, Rough whereas that of Hornfels is Granular, Platy. Picrite appears Rough and Shiny and Hornfels appears Dull. The luster of Picrite is subvitreous to dull while that of Hornfels is shiny. Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors whereas Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. The commercial uses of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo) and that of Hornfels are cemetery markers, commemorative tablets, creating artwork.