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
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
Discoverer
Unknown
Unknown
Etymology
From English feldspar and -ite
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
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, Opaque Rock
Texture
Arborescent Patterned, Vitreous
Earthy
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black to Grey, Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Skeletal
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
Medical Industry
Surgery
Not Yet Used
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Mirror, Jewelry
Cemetery Markers, Creating Artwork
Types
Not Available
Not Available
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Available in Lots of Colors and Patterns
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Figurines
Not Yet Used
Not Yet Used
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.
Rhyodacite 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.
Mineral Content
Feldspar, Iron Oxides
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, Fe, Potassium Oxide, NA, Potassium, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Greasy to Dull
Cleavage
Non-Existent
Not Available
Toughness
Not Available
2.1
Specific Gravity
2.6-2.7
2.34-2.40
Transparency
Translucent
Opaque
Density
2.6 g/cm3
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Kenya
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Argentina, Chile, Ecuador, Peru
Not Yet Found
Deposits in Oceania Continent
Australia
New Zealand
Not Yet Found