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.
Flint is a hard type of sedimentary rock that produces a small piece of burning material when hit by steel
History
Origin
Tonale, Italy
-
Discoverer
Unknown
Unknown
Etymology
From Trondheim, Norway
From Old English flint - a type of rock mainly known for high hardness and for giving off sparks when struck
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Plutonic
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Banded, Rough
Color
Black, Brown, Light to Dark Grey, White
Black, Brown, Green, Grey, Red, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Banded and Foilated
Glassy or Pearly
Architecture
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Decorative Aggregates, 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
Arrowheads, Cutting Tool, Spear Points
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Other Uses
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone, In fire-starting tools, Manufacture of tools, Metallurgical Flux, Jewelry, To ignite fire, Used in flintlock firearms
Types
Intermediate intrusive rock
Chert and Jasper
Features
Is one of the oldest rock, Typically speckled black and white.
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes trondhjemite with quartz as major mineral.
Flint is formed by the decomposition and compaction of various organisms such as sponges and diatoms under the water.
Composition
Mineral Content
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
Silicon
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Physical Properties
Hardness
6-77
1
7
👆🏻
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Fracture
Conchoidal
Conchoidal
Streak
Bluish Black
White
Porosity
Very Less Porous
Highly Porous
Luster
Subvitreous to Dull
Vitreous
Compressive Strength
130.00 N/mm2450.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
2.1
1.5
Specific Gravity
2.86-32.5-2.8
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.73 g/cm32.7-2.71 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.92 kJ/Kg K0.74 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
-
Azerbaijan, China, Russia
Africa
Egypt
-
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
Austria, Belgium, Cyprus, Denmark, France, Germany, Italy, Malta, Netherlands, Poland, Portugal, Romania, Spain, Sweden, Switzerland, Turkey, Ukraine, United Kingdom
Others
-
-
Deposits in Western Continents
North America
USA
USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Bolivia
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
New Zealand, South Australia