1 Definition
1.1 Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Trondhjemite is a leucocratic (light-colored) intrusive igneous rock. It is a variety of tonalite in which the plagioclase is mostly in the form of oligoclase. Trondhjemites are sometimes known as plagiogranites.
1.2 History
1.2.1 Origin
North America
Tonale, Italy
1.2.2 Discoverer
Ferdinand von Richthofen
Unknown
1.3 Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Not Available
1.4 Class
Igneous Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Aphanitic, Glassy, Porphyritic
Phaneritic
2.2 Color
Grey, White, Light Black
Black, Brown, Light to Dark Grey, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
Banded
Banded and Foilated
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
3.4 Other Uses
3.4.1 Commercial Uses
Gemstone, Laboratory bench tops, Jewelry
Cemetery Markers, Creating Artwork
4 Types
4.1 Types
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Not Available
4.2 Features
Acidic in nature, Available in lots of colors
Is one of the oldest rock, Typically speckled black and white.
4.3 Archaeological Significance
4.3.1 Monuments
Not Yet Used
Not Yet Used
4.3.2 Famous Monuments
Not Applicable
Not Applicable
4.3.3 Sculpture
4.3.4 Famous Sculptures
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 Formation
Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes trondhjemite with quartz as major mineral.
5.2 Composition
5.2.1 Mineral Content
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
5.2.2 Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
NaCl, CaO, MgO, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Large and Coarse Grained
Medium to Fine Coarse Grained
6.1.3 Fracture
Sub-conchoidal
Conchoidal
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Very Less Porous
6.1.6 Luster
Earthy
Subvitreous to Dull
6.1.7 Compressive Strength
6.1.8 Cleavage
Not Available
Not Available
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
2.4-2.6 g/cm32.73 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
China, India
Not Yet Found
7.1.2 Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Egypt
7.1.3 Europe
Germany, Iceland, Ireland, Italy, Spain
Finland, Germany, Italy, Romania, Sweden, Turkey
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
7.3 Deposits in Oceania Continent
7.3.1 Australia
New Zealand, Queensland, Western Australia
New Zealand, South Australia, Western Australia