Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Rhyolite is a fine-grained igneous rock which is rich in silica
Discoverer
Unknown
Ferdinand von Richthofen
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Quench
Aphanitic, Glassy, Porphyritic
Color
Black, Brown, Colourless, Green, Grey, Pink, White
Grey, White, Light Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Banded
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
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, Making natural cement
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments
Artifacts
Commercial Uses
Creating Artwork, Gemstone
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
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Figurines
Not Yet Used
Not Yet Used
Formation
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
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
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact 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
Very fine-grained
Large and Coarse Grained
Fracture
Uneven
Sub-conchoidal
Streak
Light to dark brown
Colorless
Porosity
Less Porous
Highly Porous
Cleavage
Irregular
Not Available
Toughness
Not Available
2
Specific Gravity
2.46-2.86
2.65-2.67
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
2.4-2.6 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
South Korea
China, India
Africa
Western Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Great Britain, Switzerland
Germany, Iceland, Ireland, Italy, Spain
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Not Yet Found
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
All about Pseudotachylite and Rhyolite Properties
Know all about Pseudotachylite and Rhyolite properties here. All properties of rocks are important as they define the type of rock and its application. Pseudotachylite belongs to Metamorphic Rocks while Rhyolite belongs to Igneous Rocks.Texture of Pseudotachylite is Quench whereas that of Rhyolite is Aphanitic, Glassy, Porphyritic. Pseudotachylite appears Dull and Soft and Rhyolite appears Banded. The luster of Pseudotachylite is vitreous while that of Rhyolite is earthy. Pseudotachylite is available in black, brown, colourless, green, grey, pink, white colors whereas Rhyolite is available in grey, white, light black colors. The commercial uses of Pseudotachylite are creating artwork, gemstone and that of Rhyolite are gemstone, laboratory bench tops, jewelry.