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.
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Origin
Tonale, Italy
New Zealand
Discoverer
Unknown
Unknown
Etymology
Not Available
From Greek mulōn mill + -ite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness 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
Foliated
Color
Black, Brown, Light to Dark Grey, White
Black to Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded and Foilated
Dull, Banded and Foilated
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
for Road Aggregate, Landscaping, Roadstone
Medical Industry
Not Available
Not Available
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone, Jewelry
Types
Not Available
Blastomylonites, Ultramylonites and Phyllonites
Features
Is one of the oldest rock, Typically speckled black and white.
Surfaces are often shiny
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Not Available
Famous Sculptures
Not Available
Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Formation
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes trondhjemite with quartz as major mineral.
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Mineral Content
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
Porphyroblasts
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Streak
Bluish Black
White
Porosity
Very Less Porous
Highly Porous
Luster
Subvitreous to Dull
Shiny
Compressive Strength
Not Available
Cleavage
Not Available
Conchoidal
Toughness
2.1
Not Available
Specific Gravity
2.86-3
2.97-3.05
Transparency
Opaque
Opaque
Density
2.73 g/cm3
2.6-4.8 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Not Available
China, India, Indonesia, Saudi Arabia, South Korea
Africa
Egypt
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Others
Not Available
Not Available
Deposits in Western Continents
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Not Available
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
Central Australia, Western Australia
Trondhjemite vs Mylonite 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 Mylonite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Trondhjemite and Properties of Mylonite. Learn more about Trondhjemite vs Mylonite in the next section. The interior uses of Trondhjemite include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Mylonite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Trondhjemite and Mylonite, 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 Mylonite include For road aggregate, Landscaping, Roadstone.
More about Trondhjemite and Mylonite
Here you can know more about Trondhjemite and Mylonite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Trondhjemite and Mylonite 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 Mylonite includes Porphyroblasts. You can also check out the list of all Igneous Rocks. When we have to compare Trondhjemite vs Mylonite, 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, Mylonite is available in black to grey colors. Appearance of Trondhjemite is Banded and Foilated and that of Mylonite is Dull, Banded and Foilated. Properties of rock is another aspect for Trondhjemite vs Mylonite. The hardness of Trondhjemite is 6-7 and that of Mylonite is 3-4. The types of Trondhjemite are Not Available whereas types of Mylonite are Blastomylonites, Ultramylonites and Phyllonites. 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 Mylonite is white. The specific heat capacity of Trondhjemite is 0.92 kJ/Kg K and that of Mylonite is 1.50 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 Mylonite is heat resistant, impact resistant, pressure resistant.
