Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Whiteschist is an uncommon rock type belonging to a class of metamorphic rock, this is formed at high-ultra-high pressures
Origin
Romania and Moldova, Europe
Tasmania
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 schiste, Greek skhistos i.e. split
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
Group
Volcanic
Not Applicable
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Foliated
Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
Colourless, Green, Grey, White
Durability
Durable
Durable
Appearance
Vesicular
Banded and Foilated
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Commemorative Tablets, Creating Artwork
Creating Artwork, Gemstone, Jewelry, Production of Lime
Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Not Available
Features
Host Rock for Lead, Is one of the oldest rock
High percentage of mica, Host Rock for Lead
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Figurines
Not Yet Used
Used
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.
Whiteschist is formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Carbonate, Coesite, Quartz, Silica
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
CaO, Mg, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Fine Coarse Grained
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Porosity
Less Porous
Less Porous
Luster
Subvitreous to Dull
Subvitreous to Dull
Compressive Strength
Not Available
Toughness
Not Available
1
Specific Gravity
2.86-2.87
2.86
Transparency
Translucent
Opaque
Density
2.77-2.771 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
Not Yet Found
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
France, Greece, Romania, Scotland, Spain
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
New South Wales, New Zealand, Queensland