Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
History
Origin
-
Pennines, England
Discoverer
Alexandre Brongniart and René Just Haüy
J.J. Ferber
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Grit + Stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Earthy
Color
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Banded
Layered and Foliated
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
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
Construction Aggregate, Roadstone
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Cemetery Markers, Creating Artwork
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Types
Felsic volcanic rock
Sedimentary rock
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Available in Lots of Colors and Patterns, Generally rough to touch, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
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.
Gritstone is a type of sedimentary rock which was formed on the floors of wide river deltas where the grit deposits were laid down, with every tide or flood dumping another layer of sediment.
Composition
Mineral Content
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Calcite, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion
Physical Properties
Hardness
66-7
1
7
👆🏻
Grain Size
Fine Grained
Coarse Grained
Fracture
-
Conchoidal
Streak
White
White
Porosity
Less Porous
Highly Porous
Luster
Metallic
Dull
Compressive Strength
150.00 N/mm270.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
-
-
Specific Gravity
2.72.250
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.43-2.45 g/cm32.2 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.84 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
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
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Namibia, Nigeria, South Africa
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
Austria, Denmark, Germany, Great Britain, Netherlands, Poland, Sweden, Switzerland, United Kingdom
Others
-
Greenland
Deposits in Western Continents
North America
USA
Canada, USA
South America
Brazil, Chile
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
New South Wales, New Zealand, Western Australia