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Porphyry and Lignite


Lignite and Porphyry


Definition

Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix   
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat   

History
  
  

Origin
Egypt   
France   

Discoverer
Unknown   
Unknown   

Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites   
From French, Latin lignum wood + -ite1   

Class
Igneous Rocks   
Sedimentary Rocks   

Sub-Class
Durable Rock, Hard Rock   
Durable Rock, Soft Rock   

Family
  
  

Group
Plutonic   
Not Applicable   

Other Categories
Fine Grained Rock, Opaque Rock   
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock   

Texture

Texture
Porphyritic   
Amorphous, Glassy   

Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White   
Black, Brown, Dark Brown, Grey, Light to Dark Grey   

Maintenance
Less   
Less   

Durability
Durable   
Durable   

Water Resistant
No   
No   

Scratch Resistant
Yes   
No   

Stain Resistant
Yes   
No   

Wind Resistant
No   
No   

Acid Resistant
Yes   
No   

Appearance
Dull   
Veined or Pebbled   

Uses

Architecture
  
  

Interior Uses
Decorative Aggregates, Interior Decoration   
Not Yet Used   

Exterior Uses
Garden Decoration, Paving Stone   
Not Yet Used   

Other Architectural Uses
Curbing   
Not Yet Used   

Industry
  
  

Construction Industry
Construction Aggregate   
for Road Aggregate, Steel Production   

Medical Industry
Not Yet Used   
Not Yet Used   

Antiquity Uses
Artifacts, Monuments, Sculpture   
Not Yet Used   

Other Uses
  
  

Commercial Uses
Creating Artwork, Gemstone, Jewelry   
Electricity Generation   

Types

Types
Rhomb Porphyry   
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite   

Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny   
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel   

Archaeological Significance
  
  

Monuments
Used   
Not Yet Used   

Famous Monuments
Data Not Available   
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   
Present   

Formation

Formation
Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.   
Coal formation takes place due to accumulation of plant debris in a swamp environment. The Coal formation process continues, as peat turns into lignite brown or black coal at increasing heat and pressure.   

Composition
  
  

Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica   
Not Available   

Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide   
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur   

Transformation
  
  

Metamorphism
Yes   
No   

Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism   
Not Applicable   

Weathering
Yes   
Yes   

Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered   
Biological Weathering, Chemical Weathering, Mechanical Weathering   

Erosion
Yes   
Yes   

Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion   
Chemical Erosion, Water Erosion, Wind Erosion   

Properties

Physical Properties
  
  

Hardness
6-7   
1   

Grain Size
Fine Grained   
Medium to Fine Coarse Grained   

Fracture
Irregular   
Conchoidal   

Streak
White   
Black   

Porosity
Less Porous   
Highly Porous   

Luster
Dull   
Dull to Vitreous to Submetallic   

Cleavage
Imperfect   
Non-Existent   

Toughness
1.7   
Not Available   

Specific Gravity
2.5-4   
1.1-1.4   

Transparency
Translucent to Opaque   
Opaque   

Density
2.5-2.52 g/cm3   
800-801 g/cm3   

Thermal Properties
  
  

Specific Heat Capacity
Not Available   
1.26 kJ/Kg K   
5

Resistance
Heat Resistant, Impact Resistant   
Heat Resistant   

Reserves

Deposits in Eastern Continents
  
  

Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam   
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam   

Africa
Egypt, Ethiopia, Ghana, South Africa   
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania   

Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland   
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom   

Others
Greenland   
Not Yet Found   

Deposits in Western Continents
  
  

North America
Canada, Cuba, Jamaica, USA   
Canada, Mexico, USA   

South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay   
Brazil, Chile, Colombia, Venezuela   

Deposits in Oceania Continent
  
  

Australia
New South Wales, New Zealand, Western Australia   
New South Wales, Queensland, Victoria   

Summary >>
<< Reserves

All about Porphyry and Lignite Properties

Know all about Porphyry and Lignite properties here. All properties of rocks are important as they define the type of rock and its application. Porphyry belongs to Igneous Rocks while Lignite belongs to Sedimentary Rocks.Texture of Porphyry is Porphyritic whereas that of Lignite is Amorphous, Glassy. Porphyry appears Dull and Lignite appears Veined or Pebbled. The luster of Porphyry is dull while that of Lignite is dull to vitreous to submetallic. Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors whereas Lignite is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Porphyry are creating artwork, gemstone, jewelry and that of Lignite are electricity generation.

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