Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Talc carbonate is nothing but a rock sequence or a mineral composition found in metamorphic ultramafic rocks.
History
Origin
Italy
China, USA, Middle east
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From medieval Latin, talcum
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Family
Group
Volcanic
-
Other Categories
Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Very Soft
Color
Blue, Bluish - Grey
Grey, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Foliated
Soft
Architecture
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
Garden Decoration
Other Architectural Uses
Curbing
Powder
Industry
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
Source of calcium
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts
Artifacts, Jewellery, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Cemetery Markers
Manufacturing of baby powder
Types
Rhyolite
Sedimentary rock
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Easily splits into thin plates, Generally rough to touch, Host Rock for Lead
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
Formation
Comendite is a type of Igneous rock which is formed due to cooling and solidification of lava or magma. It may form with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
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
Albite, Amphibole, Quartz
Carbonate, Chlorite, Magnesium
Compound Content
Al, Fe, Potassium Oxide
CaO, Carbon Dioxide, MgO
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Water Erosion
-
Physical Properties
Hardness
6-71-2
1
7
👆🏻
Grain Size
Medium Grained
Fine Grained
Fracture
Pervasive
Flat
Streak
Bluish Black
White
Porosity
Highly Porous
Less Porous
Luster
Dull
Pearly
Compressive Strength
92.40 N/mm2250.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
2
1
Specific Gravity
2.382.86
0
8.4
👆🏻
Transparency
Opaque
Translucent
Density
-9999 g/cm32.8-2.9 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.79 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China
-
Africa
East Africa
Ethiopia, Ghana, Western Africa
Europe
Italy
England
Others
-
-
Deposits in Western Continents
North America
-
Canada, USA
South America
-
Argentina, Bolivia, Uruguay
Deposits in Oceania Continent
Australia
Queensland
Central Australia, South Australia, Western Australia