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.
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Discoverer
Unknown
Unknown
Etymology
From Trondheim, Norway
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Quench
Color
Black, Brown, Light to Dark Grey, White
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded and Foilated
Dull and Soft
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
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone
Types
Intermediate intrusive rock
Cataclastic rock
Features
Is one of the oldest rock, Typically speckled black and white.
Host Rock for Lead
Archaeological Significance
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. Pseudotachylite 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
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
-
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Fracture
Conchoidal
Uneven
Streak
Bluish Black
Light to dark brown
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Vitreous
Specific Gravity
2.86-3
2.46-2.86
Transparency
Opaque
Transparent to Translucent
Density
2.73 g/cm3
2.7-2.9 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Africa
Egypt
Western Africa
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
Great Britain, Switzerland
Deposits in Western Continents
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
-
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
Central Australia, Western Australia
Trondhjemite vs Pseudotachylite 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 Pseudotachylite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Trondhjemite and Properties of Pseudotachylite. Learn more about Trondhjemite vs Pseudotachylite in the next section. The interior uses of Trondhjemite include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Trondhjemite and Pseudotachylite, 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 Pseudotachylite include As dimension stone, Cement manufacture, For road aggregate, Making natural cement.
More about Trondhjemite and Pseudotachylite
Here you can know more about Trondhjemite and Pseudotachylite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Trondhjemite and Pseudotachylite 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 Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides. You can also check out the list of all Igneous Rocks. When we have to compare Trondhjemite vs Pseudotachylite, 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, Pseudotachylite is available in black, brown, green, grey, pink, white colors. Appearance of Trondhjemite is Banded and Foilated and that of Pseudotachylite is Dull and Soft. Properties of rock is another aspect for Trondhjemite vs Pseudotachylite. The hardness of Trondhjemite is 6-7 and that of Pseudotachylite is 7. The types of Trondhjemite are Intermediate intrusive rock whereas types of Pseudotachylite are Cataclastic rock. 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 Pseudotachylite is light to dark brown. The specific heat capacity of Trondhjemite is 0.92 kJ/Kg K and that of Pseudotachylite 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 Pseudotachylite is heat resistant.