Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Origin
Indonesia
Hawaii Islands
Discoverer
Cornish Gossen
Unknown
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From Greek pikros bitter + -ite, 19th century
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Rough, Sandy
Earthy, Rough
Color
Brown, Brown- Black, Gold, Green, Rust
Black, Brown, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Rough and Shiny
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, for Road Aggregate, Manufacture of Magnesium and Dolomite Refractories, Roadstone, Used for flooring, stair treads, borders and window sills.
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Types
Translocated gossan and Leakage gossan
Oceanite
Features
Clasts are smooth to touch, Easily splits into thin plates
Host Rock for Lead
Archaeological Significance
Formation
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Picrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Al, CaO, Carbon Dioxide, Mg, MgO
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
-
Biological Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Fine Grained
Fracture
Conchoidal
Uneven
Streak
White to Grey
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Metallic
Subvitreous to Dull
Specific Gravity
2.0
2.75-2.92
Transparency
Opaque
Opaque
Density
-9999 g/cm3
1.5-2.5 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
India, Russia
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
South Africa
Europe
Albania, France, Germany, Great Britain, United Kingdom
Iceland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Ecuador
Brazil
Deposits in Oceania Continent
Australia
New South Wales, South Australia, Western Australia
-
Gossan vs Picrite 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. Gossan vs Picrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Gossan and Properties of Picrite. Learn more about Gossan vs Picrite in the next section. The interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration whereas the interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Gossan and Picrite, they have various applications in construction industry. The uses of Gossan in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate and that of Picrite include As a sintering agent in steel industry to process iron ore, Cement manufacture, For road aggregate, Manufacture of magnesium and dolomite refractories, Roadstone, Used for flooring, stair treads, borders and window sills..
More about Gossan and Picrite
Here you can know more about Gossan and Picrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Gossan and Picrite consists of mineral content and compound content. The mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon and mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite. You can also check out the list of all Metamorphic Rocks. When we have to compare Gossan vs Picrite, the texture, color and appearance plays an important role in determining the type of rock. Gossan is available in brown, brown- black, gold, green, rust colors whereas, Picrite is available in black, brown, green, grey, pink, white, yellow colors. Appearance of Gossan is Dull and Banded and that of Picrite is Rough and Shiny. Properties of rock is another aspect for Gossan vs Picrite. The hardness of Gossan is 4-5 and that of Picrite is 6.8. The types of Gossan are Translocated gossan and Leakage gossan whereas types of Picrite are Oceanite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Gossan is white to grey while that of Picrite is white, greenish white or grey. The specific heat capacity of Gossan is 0.24 kJ/Kg K and that of Picrite is 0.88 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Gossan is heat resistant, impact resistant, pressure resistant whereas Picrite is heat resistant.