Definition
It is a metamorphic magnesium rich rock because it is composed of the mineral talc
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
History
Origin
USA
-
Discoverer
Unknown
R. J. Hauy
Etymology
From 17th century, because of its greasy feel and use like a soap
From Greek pegma, pegmat which means- thing joined together + -ite
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
Coarse Grained Rock, Opaque Rock
Texture
Polished
Pegmatitic
Color
Black, Black to Grey, Green, Grey
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull, Banded and Foilated
Layered, Banded, Veined and Shiny
Architecture
Interior Uses
Bathrooms, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
Medical Industry
Taken as a Supplement for Calcium or Magnesium
-
Antiquity Uses
Artifacts, Jewellery, Monuments, Sculpture
Artifacts, Sculpture, Small Figurines
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, Jewelry, Source of corundum, tourmalines, beryls and topaz
Types
Metamorphic rock
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Features
Host Rock for Lead
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
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
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.
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Composition
Mineral Content
Albite, Apatite, Biotite, Calcite, Carbonate, Clay Minerals, Hornblende, Ilmenite, Micas, Plagioclase, Pyroxene, Quartz
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Compound Content
CaO, Mg, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Transformation
Metamorphism
✔
✘
✔
✘
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
✔
✘
✔
✘
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
Physical Properties
Hardness
17
1
7
👆🏻
Grain Size
Fine Grained
Medium to Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
Black
White
Porosity
Less Porous
Less Porous
Luster
Greasy
Grainy, Pearly and Vitreous
Compressive Strength
225.00 N/mm2178.54 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
Perfect
Toughness
1
2.1
Specific Gravity
2.862.6-2.63
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.8-2.9 g/cm32.6-2.65 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.88 kJ/Kg K0.79 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Japan, North Korea, Russia, Saudi Arabia, Singapore, South Korea, Sri Lanka, Tajikistan, Thailand
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
Africa
Egypt, Ethiopia, Ghana, South Africa, Western Africa
South Africa
Europe
Austria, England, Finland, France, Germany, Greece, Spain, Sweden, Switzerland, United Kingdom
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Others
-
-
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Colombia
Brazil
Deposits in Oceania Continent
Australia
Central Australia, New Zealand, Queensland
New South Wales, Queensland, South Australia, Western Australia