Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From German which means hornstone
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Group
Volcanic
Not Applicable
Other Categories
Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Granular, Platy
Color
Blue, Bluish - Grey
Brown, Dark Greenish - Grey, Green, Reddish Brown
Durability
Durable
Durable
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
for Road Aggregate, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments
Commercial Uses
Cemetery Markers
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Rhyolite
Biotite hornfels
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Smooth to touch
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Not Yet Used
Not Yet Used
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. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Albite, Amphibole, Quartz
Andalusite
Compound Content
Al, Fe, Potassium Oxide
Fe, Mg
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Water Erosion
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium Grained
Fine Grained
Fracture
Pervasive
Conchoidal
Streak
Bluish Black
Unknown
Porosity
Highly Porous
Highly Porous
Cleavage
Not Available
Perfect
Toughness
2
Not Yet Found
Specific Gravity
2.38
3.4-3.9
Transparency
Opaque
Opaque
Density
Not Available
0.25-0.30 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
Africa
East Africa
Cameroon, East Africa, Tanzania, Western Africa
Europe
Italy
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Not Yet Found
Canada, USA
South America
Not Yet Found
Bolivia, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Queensland
New South Wales, New Zealand, Queensland, Western Australia
All about Comendite and Hornfels Properties
Know all about Comendite and Hornfels properties here. All properties of rocks are important as they define the type of rock and its application. Comendite belongs to Igneous Rocks while Hornfels belongs to Metamorphic Rocks.Texture of Comendite is Porphyritic whereas that of Hornfels is Granular, Platy. Comendite appears Foliated and Hornfels appears Dull. The luster of Comendite is dull while that of Hornfels is shiny. Comendite is available in blue, bluish - grey colors whereas Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. The commercial uses of Comendite are cemetery markers and that of Hornfels are cemetery markers, commemorative tablets, creating artwork.