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
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Discoverer
Unknown
Unknown
Etymology
From the English mud and stone, from low German mudde and stainaz
From the locality in Essex County, Massachusetts,US
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Black, Blue, Brown, Green, Grey, Orange, Red, White, Yellow
Dark Grey to Black
Durability
Durable
Durable
Appearance
Rough and Dull
Banded
Interior Uses
Decorative Aggregates, Entryways, Floor Tiles, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Roof Tiles
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
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, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Pottery
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Types
Marl, Shale and Argillite
Not Available
Features
Available in Lots of Colors and Patterns, Smooth to touch, Very fine grained rock
Is one of the oldest rock, Smooth to touch
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
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.
Essexite is a type of igneous rock, which is usually dark grey to black plutonic rock. For the formation of essexite, suitable magma with exact composition of K, Ba, Rb, Cs, Sr should be produced.
Mineral Content
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Not Available
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Dull
Not Available
Cleavage
Perfect
Not Available
Specific Gravity
2.2-2.8
Not Available
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Impact 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
Germany, Greece, Italy, Scotland, Turkey
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
New Zealand, Queensland