Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Granulite is fine to medium grained metamorphic rock with a granular of polygonal crystals.
Discoverer
Alexandre Brongniart and René Just Haüy
Unknown
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Latin granulum, a little grain or fine grained
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Granoblastic
Color
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Black, Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Veined or Pebbled
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving 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
As Dimension Stone, Building houses or walls
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Creating Artwork
Curling, Gemstone, Laboratory bench tops, Soil Conditioner, Tombstones
Types
Felsic volcanic rock
Metamorphic rock
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Clasts are smooth to touch
Archaeological Significance
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.
Granulite is a fine-grained granular metamorphic rock in which the main component minerals are feldspars and quartz and forms at high temperature and pressure conditions.
Mineral Content
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Quartz
Compound Content
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Aluminium Oxide, CaO, Carbon Dioxide, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Sulfur Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Coarse Grained
Porosity
Less Porous
Very Less Porous
Specific Gravity
2.7
2.8-3.0
Transparency
Opaque
Opaque
Density
2.43-2.45 g/cm3
3.06-3.33 g/cm3
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Angola, Egypt, Madagascar, Nigeria, South Africa
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Deposits in Western Continents
North America
USA
Canada, USA
South America
Brazil, Chile
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Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
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