Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Kimberlite is a rare, blue-tinged, coarse-grained intrusive igneous rock, which sometimes contains diamonds and is mostly found in South Africa and Siberia.
History
Origin
-
Kimberley, South Africa
Discoverer
Unknown
John W. Judd
Etymology
From German Grauwacke, from grau grey + wacke
From Kimberley + -ite, from the name of the South African town of Kimberley where the rock was first found.
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Clastic
Porphyritic
Color
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull
Dull and Banded
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing, Whetstones
Curbing
Industry
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Greywacke
Basaltic Kimberlites and Micaceous Kimberlites
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Absent
Formation
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
Kimberlite is an igneous rock and is the main source of diamonds. Its formation takes place deep beneath the Earth’s surface between 150 to 450 kilometres, and are erupted rapidly and violently.
Composition
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Garnet, Olivine, Phlogopite, Pyroxene
Compound Content
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6-76-7
1
7
👆🏻
Grain Size
Angular and Fine
Fine to Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
White
White
Porosity
Highly Porous
Very Less Porous
Luster
Dull
Subvitreous to Dull
Compressive Strength
120.00 N/mm2260.00 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
Conchoidal
Toughness
2.6
-
Specific Gravity
2.2-2.82.86-2.87
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.6-2.61 g/cm32.95-2.96 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.71 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Russia
Africa
Namibia, Nigeria, South Africa
Angola, Botswana, Cameroon, Ethiopia, South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
England, Hungary, Iceland, United Kingdom
Others
Greenland
Antarctica
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Argentina, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
New South Wales, New Zealand, South Australia, Western Australia