Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Basalt is a common extrusive igneous rock formed by the rapid cooling of basaltic lava exposed at or very near the surface of Earth
Origin
Romania and Moldova, Europe
Egypt
Discoverer
Unknown
Georgius Agricola
Etymology
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
From Late Latin Basaltes (variant of basanites ), very hard stone, which was imported from Ancient Greek Basanites
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Vesicular
Dull and Soft
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
Arrowheads, As Dimension Stone, Cobblestones, Cutting Tool, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts
Artifacts, Monuments
Commercial Uses
Commemorative Tablets, Creating Artwork
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork, Used in aquariums
Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Features
Host Rock for Lead, Is one of the oldest rock
Has High structural resistance against erosion and climate, 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
Formation
Dacitic magma is formed by the subduction of young oceanic crust under a thick felsic continental plate. Further, the Oceanic crust is hydrothermally altered as quartz and sodium are added.
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.
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Olivine, Plagioclase, Pyroxene
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion
-
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Streak
White
White to Grey
Porosity
Less Porous
Less Porous
Luster
Subvitreous to Dull
-
Specific Gravity
2.86-2.87
2.8-3
Transparency
Translucent
Opaque
Density
2.77-2.771 g/cm3
2.9-3.1 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Europe
France, Greece, Romania, Scotland, Spain
Iceland
Deposits in Western Continents
North America
USA
Canada, USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
-
All about Dacite and Basalt Properties
Know all about Dacite and Basalt properties here. All properties of rocks are important as they define the type of rock and its application. Dacite and Basalt belong to Igneous Rocks.Texture of Dacite is Aphanitic to Porphyritic whereas that of Basalt is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Dacite appears Vesicular and Basalt appears Dull and Soft. The luster of Dacite is subvitreous to dull while that of Basalt is . Dacite is available in bluish - grey, brown, grey, light to dark grey colors whereas Basalt is available in black, brown, light to dark grey colors. The commercial uses of Dacite are commemorative tablets, creating artwork and that of Basalt are an oil and gas reservoir, commemorative tablets, creating artwork, used in aquariums.