Definition
A yellow sandstone which is flexible when cut into thin strips
Rhyolite is a fine-grained igneous rock which is rich in silica
History
Origin
-
North America
Discoverer
Unknown
Ferdinand von Richthofen
Etymology
From the name of a mountain range where it was found; Itacolumi mountain in Brazil
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Clastic, Granular, Rough
Aphanitic, Glassy, Porphyritic
Color
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Grey, White, Light Black
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Rough
Banded
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
Other Architectural Uses
Curbing
-
Industry
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Other Uses
Commercial Uses
An Oil and Gas Reservoir, In aquifers, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Gemstone, Laboratory bench tops, Jewelry
Types
Sandstone
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Very fine grained rock
Acidic in nature, Available in lots of colors
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Absent
Formation
Itacolumite is a sedimentary rock which forms from cemented sand-sized clasts and is a type of sandstone.
Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.
Composition
Mineral Content
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6-76-7
1
7
👆🏻
Grain Size
Coarse or Fine
Large and Coarse Grained
Fracture
Conchoidal
Sub-conchoidal
Streak
White
-
Porosity
Highly Porous
Highly Porous
Luster
Dull
Earthy
Compressive Strength
95.00 N/mm2140.00 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
-
Toughness
2.6
2
Specific Gravity
2.2-2.82.65-2.67
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.2-2.8 g/cm32.4-2.6 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.92 kJ/Kg K0.71 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
China, India
Africa
Namibia, Nigeria, South Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Germany, Iceland, Ireland, Italy, Spain
Others
Greenland
-
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
New Zealand, Queensland, Western Australia