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.
  
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster
  
History
  
  
Origin
Tonale, Italy
  
Pennsylvania, U.S.
  
Discoverer
Unknown
  
Unknown
  
Etymology
Not Available
  
From Greek anthrakites, from anthrax, anthrak meaning coal
  
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
  
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Phaneritic
  
Amorphous, Glassy
  
Color
Black, Brown, Light to Dark Grey, White
  
Black, Brown, Dark Brown, Grey, Light to Dark Grey
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
No
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
Yes
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Banded and Foilated
  
Veined or Pebbled
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
  
Not Yet Used
  
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
  
Not Yet Used
  
Other Architectural Uses
Curbing
  
Not Yet Used
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
  
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
  
Medical Industry
Not Yet Used
  
In Chemical and Pharmaceutical Industry, Manufacture of Aspirins
  
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
  
Not Yet Used
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
  
Types
Not Available
  
Semi-anthracite and Meta-anthracite
  
Features
Is one of the oldest rock, Typically speckled black and white.
  
Helps in production of Heat and Electricity, Used as fossil fuel
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Not Yet Used
  
Famous Monuments
Not Applicable
  
Not Applicable
  
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.
  
Anthracite forms from the accumulation of plant debris in a swamp environment. When plant debris dies and falls into the swamp, the standing water of the swamp protects it from decay.
  
Composition
  
  
Mineral Content
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
  
Calcite, Clay, Clay Minerals
  
Compound Content
NaCl, CaO, MgO, Silicon Dioxide
  
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
No
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Not Applicable
  
Erosion
Yes
  
No
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Not Applicable
  
Physical Properties
  
  
Hardness
6-7
  
1-1.5
  
Grain Size
Medium to Fine Coarse Grained
  
Medium to Fine Coarse Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
Bluish Black
  
Black
  
Porosity
Very Less Porous
  
Less Porous
  
Luster
Subvitreous to Dull
  
Shiny
  
Cleavage
Not Available
  
Non-Existent
  
Toughness
2.1
  
Not Available
  
Specific Gravity
2.86-3
  
1.1-1.4
  
Transparency
Opaque
  
Opaque
  
Density
2.73 g/cm3
  
1.25-2.5 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
1.32 kJ/Kg K
  
4
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Water Resistant
  
Deposits in Eastern Continents
  
  
Asia
Not Yet Found
  
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
  
Africa
Egypt
  
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
  
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey
  
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, Mexico, USA
  
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
  
Brazil, Chile, Colombia, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
New Zealand, South Australia, Western Australia
  
New South Wales, Queensland, Victoria