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.
  
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock
  
History
  
  
Origin
Tonale, Italy
  
New Zealand
  
Discoverer
Unknown
  
Unknown
  
Etymology
Not Available
  
From German which means hornstone
  
Class
Igneous Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Soft Rock
  
Family
  
  
Group
Plutonic
  
Not Applicable
  
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Phaneritic
  
Granular, Platy
  
Color
Black, Brown, Light to Dark Grey, White
  
Brown, Dark Greenish - Grey, Green, Reddish Brown
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
Yes
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Banded and Foilated
  
Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
  
Decorative Aggregates, Flooring, Homes, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
  
for Road Aggregate, Roadstone
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
  
Artifacts, Monuments
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Types
Not Available
  
Biotite hornfels
  
Features
Is one of the oldest rock, Typically speckled black and white.
  
Smooth to touch
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Used
  
Famous Monuments
Not Applicable
  
Data Not Available
  
Sculpture
Used
  
Not Yet Used
  
Famous Sculptures
Data Not Available
  
Not Applicable
  
Pictographs
Not Used
  
Used
  
Petroglyphs
Not Used
  
Used
  
Figurines
Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
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. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
  
Composition
  
  
Mineral Content
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
  
Andalusite
  
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
  
Fe, Mg
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
6-7
  
2-3
  
Grain Size
Medium to Fine Coarse Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
Bluish Black
  
Unknown
  
Porosity
Very Less Porous
  
Highly Porous
  
Luster
Subvitreous to Dull
  
Shiny
  
Compressive Strength
Not Available
  
Cleavage
Not Available
  
Perfect
  
Toughness
2.1
  
Not Yet Found
  
Specific Gravity
2.86-3
  
3.4-3.9
  
Transparency
Opaque
  
Opaque
  
Density
2.73 g/cm3
  
0.25-0.30 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.84 kJ/Kg K
  
15
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant
  
Deposits in Eastern Continents
  
  
Asia
Not Yet Found
  
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
  
Africa
Egypt
  
Cameroon, East Africa, Tanzania, Western Africa
  
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
  
United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, USA
  
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
  
Bolivia, Brazil, Colombia, Ecuador
  
Deposits in Oceania Continent
  
  
Australia
New Zealand, South Australia, Western Australia
  
New South Wales, New Zealand, Queensland, Western Australia
  
Trondhjemite vs Hornfels 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 Hornfels characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Trondhjemite and Properties of Hornfels. Learn more about Trondhjemite vs Hornfels in the next section. The interior uses of Trondhjemite include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration whereas the interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Trondhjemite and Hornfels, 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 Hornfels include For road aggregate, Roadstone.
More about Trondhjemite and Hornfels
Here you can know more about Trondhjemite and Hornfels. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Trondhjemite and Hornfels 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 Hornfels includes Andalusite. You can also check out the list of all Igneous Rocks. When we have to compare Trondhjemite vs Hornfels, 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, Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. Appearance of Trondhjemite is Banded and Foilated and that of Hornfels is Dull. Properties of rock is another aspect for Trondhjemite vs Hornfels. The hardness of Trondhjemite is 6-7 and that of Hornfels is 2-3. The types of Trondhjemite are Not Available whereas types of Hornfels are Biotite hornfels. 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 Hornfels is unknown. The specific heat capacity of Trondhjemite is 0.92 kJ/Kg K and that of Hornfels is 0.84 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 Hornfels is heat resistant, impact resistant, pressure resistant.