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
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
Discoverer
Unknown
Unknown
Etymology
From Latin varius, speckled, variegated
From Pelos or clay in Greek
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Foliated
Color
Black, Brown, Light to Dark Grey
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Banded
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Creating Artwork
Commemorative Tablets, Creating Artwork
Types
Metamorphic rock
Metamorphic rock
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest 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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Olivine, Plagioclase, Pyroxene
Albite, Chlorite, 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, MgO
Types of 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, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
-
Medium to Fine Coarse Grained
Fracture
Conchoidal
Fibrous
Porosity
Less Porous
Highly Porous
Specific Gravity
2.8-3
3.4-3.7
Transparency
Opaque
Opaque
Density
2.9-3.1 g/cm3
0-300 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Africa
South Africa
Western Africa
Europe
Iceland
United Kingdom
Deposits in Western Continents
North America
Canada, USA
-
South America
Brazil
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
-
Central Australia, Western Australia
Variolite vs Metapelite 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 Metapelite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Variolite and Properties of Metapelite. Learn more about Variolite vs Metapelite in the next section. The interior uses of Variolite include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Metapelite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Variolite and Metapelite, 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 Metapelite include Cement manufacture, Construction aggregate, For road aggregate.
More about Variolite and Metapelite
Here you can know more about Variolite and Metapelite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Variolite and Metapelite consists of mineral content and compound content. The mineral content of Variolite includes Olivine, Plagioclase, Pyroxene and mineral content of Metapelite includes Albite, Chlorite, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Variolite vs Metapelite, 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, Metapelite is available in dark greenish - grey, green, light green, light greenish grey colors. Appearance of Variolite is Dull and Soft and that of Metapelite is Banded. Properties of rock is another aspect for Variolite vs Metapelite. The hardness of Variolite is 6 and that of Metapelite is 5-6. The types of Variolite are Metamorphic rock whereas types of Metapelite are Metamorphic rock. 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 Metapelite is . The specific heat capacity of Variolite is 0.84 kJ/Kg K and that of Metapelite is 0.72 kJ/Kg K. 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 Metapelite is heat resistant, impact resistant, pressure resistant.