Definition
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Appinite is an igneous rock in which the crystals are so fine grained that individual minerals cannot be easily distinguished
History
Origin
USA, Australia
-
Discoverer
Tornebohm
Unknown
Etymology
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
From the variety of Lamprophyre Greek lampros bright and shining + porphureos purple
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Earthy, Mud-rich, Rough
Porphyritic
Color
Black, Brown, Green, Grey, White
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull
Dull, Banded and Foilated
Architecture
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Whetstones
Industry
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, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner
Types
Endoskarns
Igneous rock
Features
Host Rock for Lead, Zinc and Copper Deposits
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
Formation
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.
The formation of Appinite takes place deep beneath the Earth’s surface at around 150 to 450 kms, and are erupted rapidly and violently.
Composition
Mineral Content
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Amphibole, Carbonate, Garnet, Micas, Olivine, Phlogopite, Pyroxene
Compound Content
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
-
Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
-
Chemical Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6.55-6
1
7
👆🏻
Grain Size
Fine Grained
Fine to Coarse Grained
Fracture
Irregular
Conchoidal
Streak
Light to dark brown
White
Porosity
Less Porous
Very Less Porous
Luster
Waxy and Dull
Subvitreous to Dull
Compressive Strength
70.00 N/mm2185.00 N/mm2
0.15
450
👆🏻
Cleavage
Slaty
Conchoidal
Toughness
2.4
-
Specific Gravity
2.862.86-2.87
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.8-2.9 g/cm32.95-2.96 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.92 kJ/Kg K0.84 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Russia
Africa
South Africa, Western Africa
Angola, Botswana, Cameroon, Ethiopia, South Africa
Europe
United Kingdom
England, Hungary, Iceland, United Kingdom
Others
-
Antarctica, Greenland
Deposits in Western Continents
North America
Canada
Canada, Mexico, USA
South America
Brazil, Colombia, Paraguay
Argentina, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, New Zealand, Queensland, South Australia, Western Australia