Definition
Boninite is a mafic extrusive rock which is high in magnesium and silica content, formed in fore-arc environments, typically during the early stages of subduction
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
Japan
USA, Australia
Discoverer
Unknown
Tornebohm
Etymology
From its occurrence in the Izu-Bonin arc south of Japan
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Earthy, Mud-rich, Rough
Color
Bluish - Grey, Brown, Green, Grey
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Dull
Interior Uses
Decorative Aggregates, Homes, Kitchens
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
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
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, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
An Oil and Gas Reservoir, Cemetery Markers, Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Features
Available in Lots of Colors and Patterns, High Mg content, Is one of the oldest rock
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Boninite is a type of Igneous rock which is formed through the cooling and solidification of lava or existing rocks.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Silicon Dioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Wind Erosion
-
Grain Size
Fine Grained
Fine Grained
Fracture
Uneven
Irregular
Streak
White
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Vitreous
Waxy and Dull
Specific Gravity
2.5-2.8
2.86
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
-
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
South Africa
South Africa, Western Africa
Europe
England, Finland, United Kingdom
United Kingdom
Others
Antarctica, Greenland
-
Deposits in Western Continents
South America
Colombia, Uruguay
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia
All about Boninite and Skarn Properties
Know all about Boninite and Skarn properties here. All properties of rocks are important as they define the type of rock and its application. Boninite belongs to Igneous Rocks while Skarn belongs to Metamorphic Rocks.Texture of Boninite is Aphanitic to Porphyritic whereas that of Skarn is Earthy, Mud-rich, Rough. Boninite appears Dull and Soft and Skarn appears Dull. The luster of Boninite is vitreous while that of Skarn is waxy and dull. Boninite is available in bluish - grey, brown, green, grey colors whereas Skarn is available in black, brown, green, grey, white colors. The commercial uses of Boninite are an oil and gas reservoir, cemetery markers, creating artwork, soil conditioner, source of magnesia (mgo) and that of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo).