Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Discoverer
Ferdinand von Richthofen
R. J. Hauy
Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
From Greek pegma, pegmat which means- thing joined together + -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic, Glassy, Porphyritic
Pegmatitic
Color
Grey, White, Light Black
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
Gemstone, Laboratory bench tops, Jewelry
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Types
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Features
Acidic in nature, Available in lots of colors
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Archaeological Significance
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.
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Mineral Content
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Types of Metamorphism
Burial Metamorphism, Cataclastic 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, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Large and Coarse Grained
Medium to Coarse Grained
Fracture
Sub-conchoidal
Conchoidal
Porosity
Highly Porous
Less Porous
Luster
Earthy
Grainy, Pearly and Vitreous
Specific Gravity
2.65-2.67
2.6-2.63
Transparency
Opaque
Translucent to Opaque
Density
2.4-2.6 g/cm3
2.6-2.65 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
South Africa
Europe
Germany, Iceland, Ireland, Italy, Spain
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Rhyolite vs Pegmatite 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. Rhyolite vs Pegmatite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rhyolite and Properties of Pegmatite. Learn more about Rhyolite vs Pegmatite in the next section. The interior uses of Rhyolite include Decorative aggregates, Homes, Hotels, Interior decoration and Kitchens whereas the interior uses of Pegmatite include Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Rhyolite and Pegmatite, they have various applications in construction industry. The uses of Rhyolite in construction industry include Arrowheads, As dimension stone, Building houses or walls, Construction aggregate, Cutting tool, For road aggregate, Knives and that of Pegmatite include As dimension stone, Building houses or walls, Construction aggregate, For road aggregate, Landscaping.
More about Rhyolite and Pegmatite
Here you can know more about Rhyolite and Pegmatite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rhyolite and Pegmatite consists of mineral content and compound content. The mineral content of Rhyolite includes Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz and mineral content of Pegmatite includes Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz. You can also check out the list of all Igneous Rocks. When we have to compare Rhyolite vs Pegmatite, the texture, color and appearance plays an important role in determining the type of rock. Rhyolite is available in grey, white, light black colors whereas, Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors. Appearance of Rhyolite is Banded and that of Pegmatite is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Rhyolite vs Pegmatite. The hardness of Rhyolite is 6-7 and that of Pegmatite is 7. The types of Rhyolite are Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks. whereas types of Pegmatite are Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Rhyolite is while that of Pegmatite is white. The specific heat capacity of Rhyolite is 0.71 kJ/Kg K and that of Pegmatite is 0.79 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Rhyolite is heat resistant, wear resistant whereas Pegmatite is heat resistant, impact resistant, pressure resistant.