1 Definition
1.1 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
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Latin varius, speckled, variegated
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Clastic, Polished
2.2 Color
Black, Brown, Light to Dark Grey
Dark Grey to Black, Pink, Red, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
Dull and Soft
Rough and Dull
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Homes, Interior Decoration
3.1.2 Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, Garden Decoration, Office Buildings
3.1.3 Other Architectural Uses
Curbing
Curbing, Whetstones
3.2 Industry
3.2.1 Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Used for flooring, stair treads, borders and window sills.
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture
3.4 Other Uses
3.4.1 Commercial Uses
Cemetery Markers, Creating Artwork
Fire resistant, Used to manufracture paperweights and bookends
4 Types
4.1 Types
Not Available
Not Available
4.2 Features
Has High structural resistance against erosion and climate, Very fine grained rock
Is one of the oldest rock
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Data Not Available
4.3.3 Sculpture
4.3.4 Famous Sculptures
Data Not Available
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
An argillite is a fine-grained sedimentary rock mainly composed of clay particles which forms from lithified muds which contain variable amounts of silt-sized particles.
5.2 Composition
5.2.1 Mineral Content
Olivine, Plagioclase, Pyroxene
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
5.2.2 Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Not Applicable
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Not Applicable
Chemical Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Not Applicable
Fine Grained
6.1.3 Fracture
Conchoidal
Conchoidal to Uneven
6.1.4 Streak
White to Grey
White to Grey
6.1.5 Porosity
Less Porous
Highly Porous
6.1.6 Luster
Not Available
Waxy and Dull
6.1.7 Compressive Strength
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
2.9-3.1 g/cm32.54-2.66 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
0.84 kJ/Kg K0.87 kJ/Kg K
0.14
3.2
6.2.2 Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
India, Russia
Bangladesh, China, India, Russia
7.1.2 Africa
South Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
7.1.3 Europe
Iceland
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Brazil
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
7.3 Deposits in Oceania Continent
7.3.1 Australia
Not Yet Found
New South Wales, New Zealand, Queensland, Victoria, Western Australia