1 Definition
1.1 Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
1.2 History
1.2.1 Origin
Romania and Moldova, Europe
Adak, Aleutian Islands
1.2.2 Discoverer
Unknown
Defant and Drummond
1.3 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 Adak, Aleutian Islands
1.4 Class
Igneous Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Aphanitic to Porphyritic
Porphyritic
2.2 Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
Black, Brown, Light to Dark Grey
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
3.1.2 Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Office Buildings
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts
Monuments, Sculpture, Small Figurines
3.4 Other Uses
3.4.1 Commercial Uses
Commemorative Tablets, Creating Artwork
Commemorative Tablets, Pottery, Used in aquariums
4 Types
4.1 Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Not Available
4.2 Features
Host Rock for Lead, Is one of the oldest rock
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Not Applicable
Data Not Available
4.3.3 Sculpture
4.3.4 Famous Sculptures
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
5.2 Composition
5.2.1 Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Olivine, Plagioclase, Pyroxene
5.2.2 Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
Aluminium Oxide, MgO, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion
Coastal Erosion, Sea Erosion, Water Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Medium to Fine Coarse Grained
Fine to Medium Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
6.1.6 Luster
Subvitreous to Dull
Grainy, Pearly and Vitreous
6.1.7 Compressive Strength
6.1.8 Cleavage
6.1.9 Toughness
Not Available
Not Available
6.1.10 Specific Gravity
2.86-2.87Not Available
0
8.4
6.1.11 Transparency
6.1.12 Density
2.77-2.771 g/cm3Not Available
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Not Yet Found
India, Russia
7.1.2 Africa
Not Yet Found
Ethiopia, Somalia, South Africa
7.1.3 Europe
France, Greece, Romania, Scotland, Spain
Iceland
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
7.3 Deposits in Oceania Continent
7.3.1 Australia
New Zealand, South Australia, Western Australia
Not Yet Found