Definition
Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance
Rhyolite is a fine-grained igneous rock which is rich in silica
Origin
France
North America
Discoverer
Unknown
Ferdinand von Richthofen
Etymology
From Latin varius, speckled, variegated
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Aphanitic, Glassy, Porphyritic
Color
Black, Brown, Light to Dark Grey
Grey, White, Light Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Banded
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
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, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Creating Artwork
Gemstone, Laboratory bench tops, Jewelry
Types
Not Available
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Features
Has High structural resistance against erosion and climate, Very fine grained rock
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
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
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
Olivine, Plagioclase, Pyroxene
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Not Applicable
Large and Coarse Grained
Fracture
Conchoidal
Sub-conchoidal
Streak
White to Grey
Colorless
Porosity
Less Porous
Highly Porous
Luster
Not Available
Earthy
Cleavage
Not Available
Not Available
Specific Gravity
2.8-3
2.65-2.67
Transparency
Opaque
Opaque
Density
2.9-3.1 g/cm3
2.4-2.6 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India
Africa
South Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Iceland
Germany, Iceland, Ireland, Italy, Spain
Others
Not Yet Found
Not Yet Found
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
Not Yet Found
New Zealand, Queensland, Western Australia
Variolite 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. Variolite vs Rhyolite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Variolite and Properties of Rhyolite. Learn more about Variolite vs Rhyolite in the next section. The interior uses of Variolite include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Rhyolite include Decorative aggregates, Homes, Hotels, Interior decoration and Kitchens. Due to some exceptional properties of Variolite and Rhyolite, they have various applications in construction industry. The uses of Variolite in construction industry include As dimension stone, Cobblestones, Rail track ballast, Roadstone and that of Rhyolite include Arrowheads, As dimension stone, Building houses or walls, Construction aggregate, Cutting tool, For road aggregate, Knives.
More about Variolite and Rhyolite
Here you can know more about Variolite and Rhyolite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Variolite and Rhyolite consists of mineral content and compound content. The mineral content of Variolite includes Olivine, Plagioclase, Pyroxene and mineral content of Rhyolite includes Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz. You can also check out the list of all . When we have to compare Variolite vs Rhyolite, the texture, color and appearance plays an important role in determining the type of rock. Variolite is available in black, brown, light to dark grey colors whereas, Rhyolite is available in grey, white, light black colors. Appearance of Variolite is Dull and Soft and that of Rhyolite is Banded. Properties of rock is another aspect for Variolite vs Rhyolite. The hardness of Variolite is 6 and that of Rhyolite is 6-7. The types of Variolite 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 Variolite is white to grey while that of Rhyolite is colorless. The specific heat capacity of Variolite is 0.84 kJ/Kg K 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.Variolite is heat resistant, pressure resistant, wear resistant whereas Rhyolite is heat resistant, wear resistant.