Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Discoverer
Alexandre Brongniart and René Just Haüy
Unknown
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Banded, Rough
Color
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Glassy or Pearly
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
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
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Felsic volcanic rock
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
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.
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
Mineral Content
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Quartz, Silicon
Compound Content
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion
Grain Size
Fine Grained
Very fine-grained
Fracture
-
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Metallic
Waxy and Dull
Specific Gravity
2.7
2.5-2.8
Transparency
Opaque
Translucent to Opaque
Density
2.43-2.45 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Kenya, Morocco, South Africa, Tanzania
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Brazil, Chile
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Trachyte vs Chert Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Trachyte vs Chert characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Trachyte and Properties of Chert. Learn more about Trachyte vs Chert in the next section. The interior uses of Trachyte include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Chert include Decorative aggregates and Homes. Due to some exceptional properties of Trachyte and Chert, they have various applications in construction industry. The uses of Trachyte in construction industry include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Manufacture of magnesium and dolomite refractories and that of Chert include Arrowheads, Construction aggregate, Cutting tool, Spear points.
More about Trachyte and Chert
Here you can know more about Trachyte and Chert. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Trachyte and Chert consists of mineral content and compound content. The mineral content of Trachyte includes Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz and mineral content of Chert includes Quartz, Silicon. You can also check out the list of all Igneous Rocks. When we have to compare Trachyte vs Chert, the texture, color and appearance plays an important role in determining the type of rock. Trachyte is available in black, brown, dark greenish - grey, green, grey, light to dark grey, white colors whereas, Chert is available in black, brown, green, grey, red, white colors. Appearance of Trachyte is Banded and that of Chert is Glassy or Pearly. Properties of rock is another aspect for Trachyte vs Chert. The hardness of Trachyte is 6 and that of Chert is 6.5-7. The types of Trachyte are Felsic volcanic rock whereas types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Trachyte and Chert is white. The specific heat capacity of Trachyte is 0.84 kJ/Kg K and that of Chert is 0.74 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Trachyte is heat resistant, impact resistant, wear resistant whereas Chert is heat resistant, impact resistant, pressure resistant, wear resistant.