Definition
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
Rhyolite is a fine-grained igneous rock which is rich in silica
Origin
Unknown
North America
Discoverer
Unknown
Ferdinand von Richthofen
Etymology
From the mineral feldspathoid which is the main content of rock
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Earthy
Aphanitic, Glassy, Porphyritic
Color
Black, Brown, Colourless, Green, Grey, Pink, White
Grey, White, Light Black
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
Medical Industry
Taken as a Supplement for Calcium or Magnesium
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Gemstone, Laboratory bench tops, Jewelry
Types
Not Available
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Features
Host Rock for Lead
Acidic in nature, Available in lots of colors
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Used
Not Yet Used
Formation
Foidolites 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.
Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.
Mineral Content
Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Large and Coarse Grained
Fracture
Conchoidal
Sub-conchoidal
Porosity
Very Less Porous
Highly Porous
Luster
Subvitreous to Dull
Earthy
Compressive Strength
Not Available
Cleavage
Perfect
Not Available
Toughness
Not Available
2
Specific Gravity
2.86
2.65-2.67
Transparency
Translucent
Opaque
Density
Not Available
2.4-2.6 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
South Africa, Western Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Not Yet Found
Germany, Iceland, Ireland, Italy, Spain
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Not Yet Found
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand, Queensland, Western Australia
Foidolite vs Rhyolite 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. Foidolite vs Rhyolite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Foidolite and Properties of Rhyolite. Learn more about Foidolite vs Rhyolite in the next section. The interior uses of Foidolite include Decorative aggregates and Interior decoration whereas the interior uses of Rhyolite include Decorative aggregates, Homes, Hotels, Interior decoration and Kitchens. Due to some exceptional properties of Foidolite and Rhyolite, they have various applications in construction industry. The uses of Foidolite in construction industry include As dimension stone, Cement manufacture, For road aggregate and that of Rhyolite include Arrowheads, As dimension stone, Building houses or walls, Construction aggregate, Cutting tool, For road aggregate, Knives.
More about Foidolite and Rhyolite
Here you can know more about Foidolite and Rhyolite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Foidolite and Rhyolite consists of mineral content and compound content. The mineral content of Foidolite includes Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene and mineral content of Rhyolite includes Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Foidolite vs Rhyolite, the texture, color and appearance plays an important role in determining the type of rock. Foidolite is available in black, brown, colourless, green, grey, pink, white colors whereas, Rhyolite is available in grey, white, light black colors. Appearance of Foidolite is Dull and that of Rhyolite is Banded. Properties of rock is another aspect for Foidolite vs Rhyolite. The hardness of Foidolite is 1.5 and that of Rhyolite is 6-7. The types of Foidolite are Not Available whereas types of Rhyolite are Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Foidolite is white while that of Rhyolite is colorless. The specific heat capacity of Foidolite is Not Available and that of Rhyolite is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Foidolite is heat resistant, wear resistant whereas Rhyolite is heat resistant, wear resistant.
