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
Quartzite is a non-foliated metamorphic rock that forms by the metamorphism of pure quartz Sandstone
Discoverer
Unknown
Unknown
Etymology
From Latin varius, speckled, variegated
From quartz + -ite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Foliated, Granular
Color
Black, Brown, Light to Dark Grey
Black, Blue, Brown, Green, Light Grey, Purple, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Lustrous
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Flooring, Homes
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Arrowheads, As Dimension Stone, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Creating Artwork
An Oil and Gas Reservoir, As armour rock for sea walls, Cemetery Markers, Commemorative Tablets, In aquifers, Laboratory bench tops, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones, Used in aquariums
Types
Metamorphic rock
Orthoquartzite and Metaquartzite
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
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.
Quartzite forms from sandstone and the mineral quartz being put under extreme heat and pressure.
Mineral Content
Olivine, Plagioclase, Pyroxene
Chlorite, Epidote, Hematite, Kyanite, Magnetite, Muscovite or Illite, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
-
Medium Grained
Fracture
Conchoidal
Uneven, Splintery or Conchoidal
Streak
White to Grey
White
Porosity
Less Porous
Less Porous
Specific Gravity
2.8-3
2.6-2.8
Transparency
Opaque
Transparent to Translucent
Density
2.9-3.1 g/cm3
2.32-2.42 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Israel, Russia, South Korea, Thailand, Turkey
Africa
South Africa
Ethiopia, Morocco, South Africa, Zimbabwe
Europe
Iceland
England, Italy, Norway, Scotland, Sweden, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Bahamas, Canada, USA
South America
Brazil
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
-
New Zealand, Queensland, Western Australia
All about Variolite and Quartzite Properties
Know all about Variolite and Quartzite properties here. All properties of rocks are important as they define the type of rock and its application. Variolite belongs to Igneous Rocks while Quartzite belongs to Metamorphic Rocks.Texture of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Quartzite is Foliated, Granular. Variolite appears Dull and Soft and Quartzite appears Lustrous. The luster of Variolite is while that of Quartzite is vitreous. Variolite is available in black, brown, light to dark grey colors whereas Quartzite is available in black, blue, brown, green, light grey, purple, white, yellow colors. The commercial uses of Variolite are cemetery markers, creating artwork and that of Quartzite are an oil and gas reservoir, as armour rock for sea walls, cemetery markers, commemorative tablets, in aquifers, laboratory bench tops, petroleum reservoirs, soil conditioner, source of magnesia (mgo), tombstones, used in aquariums.