Definition
Trondhjemite is a leucocratic (light-colored) intrusive igneous rock. It is a variety of tonalite in which the plagioclase is mostly in the form of oligoclase. Trondhjemites are sometimes known as plagiogranites.
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
Tonale, Italy
USA, Australia
Discoverer
Unknown
Tornebohm
Etymology
Not Available
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
Group
Plutonic
Not Applicable
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Earthy, Mud-rich, Rough
Color
Black, Brown, Light to Dark Grey, White
Black, Brown, Colourless, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded and Foilated
Dull
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
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
Medical Industry
Not Yet Used
Not Applicable
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Not Available
Endoskarns
Features
Is one of the oldest rock, Typically speckled black and white.
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes trondhjemite with quartz as major mineral.
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
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Not Applicable
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
Bluish Black
Light to dark brown
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Waxy and Dull
Cleavage
Not Available
Slaty
Specific Gravity
2.86-3
2.86
Transparency
Opaque
Opaque
Density
2.73 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
Egypt
South Africa, Western Africa
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
Central Australia, Western Australia
Trondhjemite vs Skarn 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. Trondhjemite vs Skarn characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Trondhjemite and Properties of Skarn. Learn more about Trondhjemite vs Skarn in the next section. The interior uses of Trondhjemite include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Trondhjemite and Skarn, they have various applications in construction industry. The uses of Trondhjemite in construction industry include As dimension stone, Cement manufacture, Cobblestones, Construction aggregate, For road aggregate and that of Skarn include 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.
More about Trondhjemite and Skarn
Here you can know more about Trondhjemite and Skarn. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Trondhjemite and Skarn consists of mineral content and compound content. The mineral content of Trondhjemite includes Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon and mineral content of Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite. You can also check out the list of all Igneous Rocks. When we have to compare Trondhjemite vs Skarn, the texture, color and appearance plays an important role in determining the type of rock. Trondhjemite is available in black, brown, light to dark grey, white colors whereas, Skarn is available in black, brown, colourless, green, grey, white colors. Appearance of Trondhjemite is Banded and Foilated and that of Skarn is Dull. Properties of rock is another aspect for Trondhjemite vs Skarn. The hardness of Trondhjemite is 6-7 and that of Skarn is 6.5. The types of Trondhjemite are Not Available whereas types of Skarn are Endoskarns. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Trondhjemite is bluish black while that of Skarn is light to dark brown. The specific heat capacity of Trondhjemite is 0.92 kJ/Kg K and that of Skarn 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.Trondhjemite is heat resistant, pressure resistant, wear resistant whereas Skarn is heat resistant.
