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
Diabase is a fine-grained igneous rock which is composed mostly of pyroxene and feldspar
Discoverer
Unknown
Christian Leopold von Buch
Etymology
From Latin varius, speckled, variegated
From Greek di + base
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Aphanitic, Granular
Color
Black, Brown, Light to Dark Grey
Dark Grey to Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Vesicular
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Homes, Interior Decoration, Kitchens
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Creating Artwork
An Oil and Gas Reservoir, Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Not Available
Not Available
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Smooth to touch
Archaeological Significance
Famous Monuments
Data Not Available
Stonehenge in English county of Wiltshire
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not 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.
Diabase forms when molten igneous rock is squeezed up into a vertical crack in other rocks, the crack is usually forced apart and the molten rock cools in the space to form a tabular igneous intrusion cutting across the surrounding rocks and is known as a dike.
Mineral Content
Olivine, Plagioclase, Pyroxene
Augite, Chlorite, Olivine, Plagioclase, Pyroxene, Pyrrhotite, Serpentine
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Not Applicable
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
Black
Porosity
Less Porous
Highly Porous
Luster
Not Available
Not Available
Cleavage
Not Available
Not Available
Specific Gravity
2.8-3
2.86-2.87
Transparency
Opaque
Opaque
Density
2.9-3.1 g/cm3
2.7-3.3 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
South Africa
South Africa, Tanzania
Europe
Iceland
Germany, Greece, Italy, Scotland, Turkey
Others
Not Yet Found
Antarctica, Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Argentina, Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
Not Yet Found
Central Australia, New Zealand, Queensland, Western Australia
All about Variolite and Diabase Properties
Know all about Variolite and Diabase properties here. All properties of rocks are important as they define the type of rock and its application. Variolite and Diabase belong to Igneous Rocks.Texture of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Diabase is Aphanitic, Granular. Variolite appears Dull and Soft and Diabase appears Vesicular. The luster of Variolite and Diabase is not available. Variolite is available in black, brown, light to dark grey colors whereas Diabase is available in dark grey to black colors. The commercial uses of Variolite are cemetery markers, creating artwork and that of Diabase are an oil and gas reservoir, cemetery markers, commemorative tablets, laboratory bench tops, jewelry, sea defence, tombstones.