Definition
Diabase is a fine-grained igneous rock which is composed mostly of pyroxene and feldspar
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
History
Origin
Germany
-
Discoverer
Christian Leopold von Buch
Unknown
Etymology
From Greek di + base
From German Grauwacke, from grau grey + wacke
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic, Granular
Clastic
Color
Dark Grey to Black
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Vesicular
Dull
Architecture
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration, Kitchens
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing, Whetstones
Industry
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture, Small Figurines
Other Uses
Commercial Uses
An Oil and Gas Reservoir, Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Types
Dolerite
Greywacke
Features
Smooth to touch
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
Monuments
-
-
Famous Monuments
Stonehenge in English county of Wiltshire
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
Diabase forms when molten igneous rock is squeezed up into a vertical crack in other rocks, the crack is usually forced apart and the molten rock cools in the space to form a tabular igneous intrusion cutting across the surrounding rocks and is known as a dike.
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.
Composition
Mineral Content
Augite, Chlorite, Olivine, Plagioclase, Pyroxene, Pyrrhotite, Serpentine
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
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
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Physical Properties
Hardness
76-7
1
7
👆🏻
Grain Size
Fine to Medium Grained
Angular and Fine
Fracture
Conchoidal
Conchoidal
Streak
Black
White
Porosity
Highly Porous
Highly Porous
Luster
-
Dull
Compressive Strength
225.00 N/mm2120.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
1.6
2.6
Specific Gravity
2.86-2.872.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.7-3.3 g/cm32.6-2.61 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.84 kJ/Kg K0.71 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
India
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
South Africa, Tanzania
Namibia, Nigeria, South Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Antarctica, Greenland
Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Argentina, Brazil, Colombia, Venezuela
Brazil
Deposits in Oceania Continent
Australia
Central Australia, New Zealand, Queensland, Western Australia
New South Wales, New Zealand