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Soapstone and Porphyry


Porphyry and Soapstone


Definition

Definition
It is a metamorphic magnesium rich rock because it is composed of the mineral talc  
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix  

History
  
  

Origin
USA  
Egypt  

Discoverer
Unknown  
Unknown  

Etymology
From 17th century, because of its greasy feel and use like a soap  
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites  

Class
Metamorphic Rocks  
Igneous Rocks  

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

Family
  
  

Group
-  
Plutonic  

Other Categories
Fine Grained Rock, Opaque Rock  
Fine Grained Rock, Opaque Rock  

Texture

Texture
Polished  
Porphyritic  

Color
Black, Black to Grey, Green, Grey  
Black, Brown, Green, Grey, Red, Rust, White  

Maintenance
Less  
Less  

Durability
Durable  
Durable  

Water Resistant
Yes  
No  

Scratch Resistant
No  
Yes  

Stain Resistant
No  
Yes  

Wind Resistant
No  
No  

Acid Resistant
No  
Yes  

Appearance
Dull, Banded and Foilated  
Dull  

Uses

Architecture
  
  

Interior Uses
Bathrooms, Decorative Aggregates, Homes, Interior Decoration  
Decorative Aggregates, Interior Decoration  

Exterior Uses
As Facing Stone, Garden Decoration  
Garden Decoration, Paving Stone  

Other Architectural Uses
Curbing  
Curbing  

Industry
  
  

Construction Industry
Manufacture of Magnesium and Dolomite Refractories  
Construction Aggregate  

Medical Industry
Taken as a Supplement for Calcium or Magnesium  
-  

Antiquity Uses
Artifacts, Jewellery, Monuments, Sculpture  
Artifacts, Monuments, Sculpture  

Other Uses
  
  

Commercial Uses
Cemetery Markers, Creating Artwork, Gemstone, Jewelry, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Production of Lime, Source of Magnesia (MgO)  
Creating Artwork, Gemstone, Jewelry  

Types

Types
Metamorphic rock  
Rhomb Porphyry  

Features
Host Rock for Lead  
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny  

Archaeological Significance
  
  

Monuments
-  
-  

Famous Monuments
Christ the Redeemer in Rio de Janeiro, Stonehenge in English county of Wiltshire  
-  

Sculpture
-  
-  

Famous Sculptures
-  
-  

Pictographs
-  
-  

Petroglyphs
-  
-  

Figurines
-  
-  

Fossils
Absent  
Absent  

Formation

Formation
Soapstone is a talc-schist, which is a type of metamorphic rock and it is largely composed of the mineral talc and is thus rich inmagnesium.   
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.  

Composition
  
  

Mineral Content
Albite, Apatite, Biotite, Calcite, Carbonate, Clay Minerals, Hornblende, Ilmenite, Micas, Plagioclase, Pyroxene, Quartz  
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica  

Compound Content
CaO, Mg, MgO  
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide  

Transformation
  
  

Metamorphism
Yes  
Yes  

Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism  

Weathering
No  
Yes  

Types of Weathering
-  
Biological Weathering, Chemical Weathering  

Erosion
No  
Yes  

Types of Erosion
-  
Chemical Erosion, Coastal Erosion, Glacier Erosion  

Properties

Physical Properties
  
  

Hardness
1  
6-7  

Grain Size
Fine Grained  
Fine Grained  

Fracture
Conchoidal  
Irregular  

Streak
Black  
White  

Porosity
Less Porous  
Less Porous  

Luster
Greasy  
Dull  

Compressive Strength
225.00 N/mm2  
8
150.00 N/mm2  
22

Cleavage
Perfect  
-  

Toughness
1  
1.7  

Specific Gravity
2.86  
2.5-4  

Transparency
Opaque  
Translucent to Opaque  

Density
2.8-2.9 g/cm3  
2.5-2.52 g/cm3  

Thermal Properties
  
  

Specific Heat Capacity
0.88 kJ/Kg K  
13
0.71 kJ/Kg K  
23

Resistance
Heat Resistant, Pressure Resistant  
Heat Resistant, Impact Resistant  

Reserves

Deposits in Eastern Continents
  
  

Asia
China, India, Indonesia, Japan, North Korea, Russia, Saudi Arabia, Singapore, South Korea, Sri Lanka, Tajikistan, Thailand  
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam  

Africa
Egypt, Ethiopia, Ghana, South Africa, Western Africa  
Egypt, Ethiopia, Ghana, South Africa  

Europe
Austria, England, Finland, France, Germany, Greece, Spain, Sweden, Switzerland, United Kingdom  
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland  

Others
-  
Greenland  

Deposits in Western Continents
  
  

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

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

Deposits in Oceania Continent
  
  

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

Summary >>
<< Reserves

All about Soapstone and Porphyry Properties

Know all about Soapstone and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Soapstone belongs to Metamorphic Rocks while Porphyry belongs to Igneous Rocks.Texture of Soapstone is Polished whereas that of Porphyry is Porphyritic. Soapstone appears Dull, Banded and Foilated and Porphyry appears Dull. The luster of Soapstone is greasy while that of Porphyry is dull. Soapstone is available in black, black to grey, green, grey colors whereas Porphyry is available in black, brown, green, grey, red, rust, white colors. The commercial uses of Soapstone and Porphyry are cemetery markers, creating artwork, gemstone, jewelry, manufacture of soap, solvents, dyes, plastics and fibres, production of lime, source of magnesia (mgo).

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