Definition
Basalt is a common extrusive igneous rock formed by the rapid cooling of basaltic lava exposed at or very near the surface of Earth
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Discoverer
Georgius Agricola
Johann Gottlob Lehmann
Etymology
From Late Latin Basaltes (variant of basanites ), very hard stone, which was imported from Ancient Greek Basanites
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Clastic, Splintery
Color
Black, Brown, Light to Dark Grey
Black, Brown, Buff, Green, Grey, Red, Yellow
Durability
Durable
Durable
Appearance
Dull and Soft
Muddy
Interior Uses
Floor Tiles, Homes, Hotels, Kitchens
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
Arrowheads, As Dimension Stone, Cobblestones, Cutting Tool, Rail Track Ballast, Roadstone
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments
Artifacts, Sculpture
Commercial Uses
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork, Used in aquariums
Creating Artwork, Pottery
Types
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Archaeological Significance
Famous Monuments
Easter Island in the Polynesian Triangle, Pacific Ocean, Gateway of India in Mumbai, India, Gol Gumbaz in Karnataka, India
Jantar Mantar in India
Formation
Basalt forms when lava reaches the Earth's surface near an active volcano. The temperature of lava is between 1100 to 1250° C when it gets to the surface.
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
Mineral Content
Olivine, Plagioclase, Pyroxene
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, Fe, Mg, Silicon Dioxide, Sodium
Types of Metamorphism
Contact Metamorphism
-
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Fine Grained
Very fine-grained
Streak
White to Grey
White
Porosity
Less Porous
Highly Porous
Specific Gravity
2.8-3
2.2-2.8
Transparency
Opaque
Opaque
Density
2.9-3.1 g/cm3
2.4-2.8 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
India, Russia
Bangladesh, China, India, Russia
Africa
South Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Iceland
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
North America
Canada, USA
USA
South America
Brazil
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland, Victoria, Western Australia
All about Basalt and Shale Properties
Know all about Basalt and Shale properties here. All properties of rocks are important as they define the type of rock and its application. Basalt belongs to Igneous Rocks while Shale belongs to Sedimentary Rocks.Texture of Basalt is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Shale is Clastic, Splintery. Basalt appears Dull and Soft and Shale appears Muddy. The luster of Basalt is while that of Shale is dull. Basalt is available in black, brown, light to dark grey colors whereas Shale is available in black, brown, buff, green, grey, red, yellow colors. The commercial uses of Basalt are an oil and gas reservoir, commemorative tablets, creating artwork, used in aquariums and that of Shale are creating artwork, pottery.