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
All about Felsite and Adakite Properties
Know all about Felsite and Adakite properties here. All properties of rocks are important as they define the type of rock and its application. Felsite and Adakite belong to Igneous Rocks.Texture of Felsite is Arborescent Patterned, Vitreous whereas that of Adakite is Porphyritic. Felsite appears Layered, Banded, Veined and Shiny and Adakite appears Dull and Soft. The luster of Felsite is vitreous while that of Adakite is grainy, pearly and vitreous. 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. The commercial uses of Felsite are mirror, jewelry and that of Adakite are commemorative tablets, pottery, used in aquariums.