Definition
Mudstone is a fine-grained, dark gray sedimentary rock, which is formed from silt and clay and is similar to shale but has less laminations
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
Discoverer
Unknown
Unknown
Etymology
From the English mud and stone, from low German mudde and stainaz
From Latin varius, speckled, variegated
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
Texture
Clastic
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Black, Blue, Brown, Green, Grey, Orange, Red, White, Yellow
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Rough and Dull
Dull and Soft
Interior Uses
Decorative Aggregates, Entryways, Floor Tiles, Interior Decoration
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Roof Tiles
Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Pottery
Cemetery Markers, Creating Artwork
Types
Marl, Shale and Argillite
Not Available
Features
Available in Lots of Colors and Patterns, Smooth to touch, Very fine grained rock
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Formation
Mudstone forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are buried and compacted by overlying sediment hence forming mudstone.
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
Mineral Content
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion
Not Applicable
Grain Size
Very fine-grained
Not Applicable
Fracture
Not Available
Conchoidal
Streak
White
White to Grey
Porosity
Highly Porous
Less Porous
Luster
Dull
Not Available
Compressive Strength
Not Available
Cleavage
Perfect
Not Available
Specific Gravity
2.2-2.8
2.8-3
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
2.9-3.1 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
India, Russia
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
South Africa
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Iceland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Not Yet Found
All about Mudstone and Variolite Properties
Know all about Mudstone and Variolite properties here. All properties of rocks are important as they define the type of rock and its application. Mudstone belongs to Sedimentary Rocks while Variolite belongs to Igneous Rocks.Texture of Mudstone is Clastic whereas that of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Mudstone appears Rough and Dull and Variolite appears Dull and Soft. The luster of Mudstone is dull while that of Variolite is not available. Mudstone is available in black, blue, brown, green, grey, orange, red, white, yellow colors whereas Variolite is available in black, brown, light to dark grey colors. The commercial uses of Mudstone are creating artwork, pottery and that of Variolite are cemetery markers, creating artwork.