Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Origin
Romania and Moldova, Europe
-
Discoverer
Unknown
Unknown
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 French anorthose plagioclase + -ite1
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
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Foliated, Glassy
Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Durability
Durable
Durable
Appearance
Vesicular
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
As Dimension Stone, Cement Manufacture, for Road Aggregate
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
Commemorative Tablets, Creating Artwork
Creating Artwork, Curling
Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Proterozoic Anorthosite and Archean Anorthosite
Features
Host Rock for Lead, Is one of the oldest rock
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
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.
Anorthosite is a phaneritic, intrusive igneous rock which is characterized by a predominance of plagioclase feldspar which is almost 90–100%, and a minimal mafic component.
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Coarse Grained
Fracture
Conchoidal
Irregular
Porosity
Less Porous
Less Porous
Luster
Subvitreous to Dull
Pearly to Subvitreous
Specific Gravity
2.86-2.87
2.62-2.82
Transparency
Translucent
Translucent
Density
2.77-2.771 g/cm3
2.7-4 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Europe
France, Greece, Romania, Scotland, Spain
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Deposits in Western Continents
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Bolivia, Colombia
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
Central Australia, South Australia, Western Australia
All about Dacite and Anorthosite Properties
Know all about Dacite and Anorthosite properties here. All properties of rocks are important as they define the type of rock and its application. Dacite and Anorthosite belong to Igneous Rocks.Texture of Dacite is Aphanitic to Porphyritic whereas that of Anorthosite is Foliated, Glassy. Dacite appears Vesicular and Anorthosite appears Layered, Banded, Veined and Shiny. The luster of Dacite is subvitreous to dull while that of Anorthosite is pearly to subvitreous. Dacite is available in bluish - grey, brown, grey, light to dark grey colors whereas Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors. The commercial uses of Dacite are commemorative tablets, creating artwork and that of Anorthosite are creating artwork, curling.