Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
Discoverer
Alexandre Brongniart and René Just Haüy
Unknown
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Pelos or clay in Greek
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Volcanic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Foliated
Color
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Creating Artwork
Commemorative Tablets, Creating Artwork
Types
Not Available
Not Available
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
Formation
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. It is the volcanic equivalent of syenite rock and forms as a result of magmatic differentiation.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Albite, Chlorite, Quartz
Compound Content
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Aluminium Oxide, CaO, MgO
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Not Available
Fibrous
Porosity
Less Porous
Highly Porous
Compressive Strength
Not Available
Cleavage
Not Available
Not Available
Toughness
Not Available
Not Available
Specific Gravity
2.7
3.4-3.7
Transparency
Opaque
Opaque
Density
2.43-2.45 g/cm3
0-300 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Not Yet Found
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Western Africa
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Not Available
South America
Brazil, Chile
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
Central Australia, Western Australia