Definition
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
Origin
-
Adak, Aleutian Islands
Discoverer
Unknown
Defant and Drummond
Etymology
From English feldspar and -ite
From Adak, Aleutian Islands
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Arborescent Patterned, Vitreous
Porphyritic
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Whetstones
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Surgery
-
Antiquity Uses
Artifacts
Monuments, Sculpture, Small Figurines
Commercial Uses
Mirror, Jewelry
Commemorative Tablets, Pottery, Used in aquariums
Types
Igneous rock
Intermediate volcanic rock
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Archaeological Significance
Formation
Felsite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
Mineral Content
Feldspar, Iron Oxides
Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Grain Size
Fine Grained
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Streak
White
Bluish Black
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Grainy, Pearly and Vitreous
Specific Gravity
2.6-2.7
-9999
Transparency
Translucent
Opaque
Density
2.6 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
India, Russia
Africa
Kenya
Ethiopia, Somalia, South Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Iceland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Argentina, Chile, Ecuador, Peru
Brazil
Deposits in Oceania Continent
Felsite vs Adakite 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. Felsite vs Adakite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Felsite and Properties of Adakite. Learn more about Felsite vs Adakite in the next section. The interior uses of Felsite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Adakite include Decorative aggregates, Floor tiles, Homes, Hotels and Kitchens. Due to some exceptional properties of Felsite and Adakite, they have various applications in construction industry. The uses of Felsite in construction industry include Arrowheads, Cutting tool, Knives, Scrapers, Spear points and that of Adakite include As dimension stone, Cobblestones, Rail track ballast, Roadstone.
More about Felsite and Adakite
Here you can know more about Felsite and Adakite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Felsite and Adakite consists of mineral content and compound content. The mineral content of Felsite includes Feldspar, Iron Oxides and mineral content of Adakite includes Olivine, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Felsite vs Adakite, the texture, color and appearance plays an important role in determining the type of rock. Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors whereas, Adakite is available in black, brown, light to dark grey colors. Appearance of Felsite is Layered, Banded, Veined and Shiny and that of Adakite is Dull and Soft. Properties of rock is another aspect for Felsite vs Adakite. The hardness of Felsite is 5-5.5 and that of Adakite is 3-4. The types of Felsite are Igneous rock whereas types of Adakite are Intermediate volcanic rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Felsite is white while that of Adakite is bluish black. The specific heat capacity of Felsite is 0.92 kJ/Kg K and that of Adakite is 0.84 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Felsite is heat resistant, impact resistant whereas Adakite is heat resistant, pressure resistant, wear resistant.