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
Pantellerite is a peralkaline rhyolite. It has a higher iron and lower aluminium composition than comendite
Origin
France
Strait of sicily
Discoverer
Unknown
Unknown
Etymology
From Latin varius, speckled, variegated
From Pantelleria, a volcanic island in the Strait of Sicily
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Eutaxitic
Color
Black, Brown, Light to Dark Grey
Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Layered and Foliated
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Not Yet Used
Exterior Uses
Garden Decoration, Office Buildings
Not Yet Used
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
NA
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork
Types
Not Available
Pantelleritic Ignimbrite
Features
Has High structural resistance against erosion and climate, Very fine grained rock
High Fe content
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.
Pantellerite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Olivine, Plagioclase, Pyroxene
Amphibole, Feldspar, Ilmenite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Al, Fe
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Not Applicable
Fine Grained
Fracture
Conchoidal
Sub-conchoidal
Streak
White to Grey
Unknown
Porosity
Less Porous
Less Porous
Luster
Not Available
Earthy
Compressive Strength
Not Available
Cleavage
Not Available
Conchoidal
Specific Gravity
2.8-3
Not Available
Transparency
Opaque
Translucent to Opaque
Density
2.9-3.1 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India
Africa
South Africa
Angola, Egypt, Madagascar, Namibia, Nigeria
Europe
Iceland
Germany, Iceland, Ireland, Italy, Spain, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Argentina, Bolivia, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Not Yet Found
Central Australia, Queensland, Western Australia