Definition
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Origin
New Zealand
Indonesia
Discoverer
Unknown
Cornish Gossen
Etymology
From Greek mulōn mill + -ite
From Cornish gossen from gos, blood from Old Cornish guit
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated
Rough, Sandy
Color
Black to Grey
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Banded and Foilated
Dull and Banded
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
for Road Aggregate, Landscaping, Roadstone
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments
Artifacts
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Cemetery Markers, Commemorative Tablets, Gemstone
Types
Blastomylonites, Ultramylonites and Phyllonites
Translocated gossan and Leakage gossan
Features
Surfaces are often shiny
Clasts are smooth to touch, Easily splits into thin plates
Archaeological Significance
Formation
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Mineral Content
Porphyroblasts
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Fine Grained
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Streak
White
White to Grey
Porosity
Highly Porous
Highly Porous
Specific Gravity
2.97-3.05
2.0
Transparency
Opaque
Opaque
Density
2.6-4.8 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Saudi Arabia, South Korea
China, India, Indonesia, Russia, Singapore, South Korea
Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Albania, France, Germany, Great Britain, United Kingdom
Deposits in Western Continents
North America
USA
Canada, USA
South America
-
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, South Australia, Western Australia
Mylonite vs Gossan 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. Mylonite vs Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Mylonite and Properties of Gossan. Learn more about Mylonite vs Gossan in the next section. The interior uses of Mylonite include Decorative aggregates and Interior decoration whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Mylonite and Gossan, they have various applications in construction industry. The uses of Mylonite in construction industry include For road aggregate, Landscaping, Roadstone and that of Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Mylonite and Gossan
Here you can know more about Mylonite and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Mylonite and Gossan consists of mineral content and compound content. The mineral content of Mylonite includes Porphyroblasts and mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon. You can also check out the list of all Metamorphic Rocks. When we have to compare Mylonite vs Gossan, the texture, color and appearance plays an important role in determining the type of rock. Mylonite is available in black to grey colors whereas, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Mylonite is Dull, Banded and Foilated and that of Gossan is Dull and Banded. Properties of rock is another aspect for Mylonite vs Gossan. The hardness of Mylonite is 3-4 and that of Gossan is 4-5. The types of Mylonite are Blastomylonites, Ultramylonites and Phyllonites whereas types of Gossan are Translocated gossan and Leakage gossan. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Mylonite is white while that of Gossan is white to grey. The specific heat capacity of Mylonite is 1.50 kJ/Kg K and that of Gossan is 0.24 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Mylonite is heat resistant, impact resistant, pressure resistant whereas Gossan is heat resistant, impact resistant, pressure resistant.