Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
  
Talc carbonate is nothing but a rock sequence or a mineral composition found in metamorphic ultramafic rocks.
  
History
  
  
Origin
Romania and Moldova, Europe
  
China, USA, Middle east
  
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 medieval Latin, talcum
  
Class
Igneous Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Soft Rock
  
Durable Rock, Soft Rock
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Aphanitic to Porphyritic
  
Very Soft
  
Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
  
Colourless, Grey, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Vesicular
  
Soft
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
  
Garden Decoration
  
Other Architectural Uses
Curbing
  
Powder
  
Industry
  
  
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
  
Source of calcium
  
Medical Industry
Not Yet Used
  
Taken as a Supplement for Calcium or Magnesium
  
Antiquity Uses
Artifacts
  
Artifacts, Jewellery, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Commemorative Tablets, Creating Artwork
  
Manufacturing of baby powder
  
Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
  
Not Available
  
Features
Host Rock for Lead, Is one of the oldest rock
  
Easily splits into thin plates, Generally rough to touch, 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
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Absent
  
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.
  
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Talc Carbonate is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
  
Composition
  
  
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
  
Carbonate, Chlorite, Magnesium
  
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
  
CaO, Carbon Dioxide, MgO
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
  
Weathering
Yes
  
No
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Not Applicable
  
Erosion
Yes
  
No
  
Types of Erosion
Chemical Erosion
  
Not Applicable
  
Physical Properties
  
  
Hardness
2-2.25
  
1-2
  
Grain Size
Medium to Fine Coarse Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Flat
  
Streak
White
  
White
  
Porosity
Less Porous
  
Less Porous
  
Luster
Subvitreous to Dull
  
Pearly
  
Compressive Strength
Not Available
  
250.00 N/mm
2
  
4
Cleavage
Perfect
  
Perfect
  
Toughness
Not Available
  
1
  
Specific Gravity
2.86-2.87
  
2.86
  
Transparency
Translucent
  
Translucent
  
Density
2.77-2.771 g/cm3
  
2.8-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
Not Yet Found
  
Not Yet Found
  
Africa
Not Yet Found
  
Ethiopia, Ghana, Western Africa
  
Europe
France, Greece, Romania, Scotland, Spain
  
England
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, USA
  
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
  
Argentina, Bolivia, Uruguay
  
Deposits in Oceania Continent
  
  
Australia
New Zealand, South Australia, Western Australia
  
Central Australia, South Australia, Western Australia