Definition
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Origin
Finland, Europe
Indonesia
Discoverer
Jakob Sederholm
Cornish Gossen
Etymology
From Finnish Rapakivi which stands for crumbly rock
From Cornish gossen from gos, blood from Old Cornish guit
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular, Phaneritic
Rough, Sandy
Color
Black, Grey, Orange, Pink, White
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined or Pebbled
Dull and Banded
Interior Uses
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
Cemetery Markers, Commemorative Tablets, Gemstone
Types
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
Translocated gossan and Leakage gossan
Features
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
Clasts are smooth to touch, Easily splits into thin plates
Archaeological Significance
Formation
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks
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
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Large and Coarse Grained
Fine to Medium Grained
Streak
White
White to Grey
Porosity
Less Porous
Highly Porous
Luster
Dull to Grainy with Sporadic parts Pearly and Vitreous
Metallic
Specific Gravity
2.6-2.7
2.0
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
China, India, Indonesia, Russia, Singapore, South Korea
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Albania, France, Germany, Great Britain, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
-
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
-
New South Wales, South Australia, Western Australia
Rapakivi Granite 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. Rapakivi Granite vs Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rapakivi Granite and Properties of Gossan. Learn more about Rapakivi Granite vs Gossan in the next section. The interior uses of Rapakivi Granite include Bathrooms, Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Rapakivi Granite and Gossan, they have various applications in construction industry. The uses of Rapakivi Granite in construction industry include As dimension stone and that of Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Rapakivi Granite and Gossan
Here you can know more about Rapakivi Granite and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rapakivi Granite and Gossan consists of mineral content and compound content. The mineral content of Rapakivi Granite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz 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 Igneous Rocks. When we have to compare Rapakivi Granite vs Gossan, the texture, color and appearance plays an important role in determining the type of rock. Rapakivi Granite is available in black, grey, orange, pink, white colors whereas, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Rapakivi Granite is Veined or Pebbled and that of Gossan is Dull and Banded. Properties of rock is another aspect for Rapakivi Granite vs Gossan. The hardness of Rapakivi Granite is 6-7 and that of Gossan is 4-5. The types of Rapakivi Granite are Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite 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 Rapakivi Granite is white while that of Gossan is white to grey. The specific heat capacity of Rapakivi Granite is 0.79 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.Rapakivi Granite is heat resistant, wear resistant whereas Gossan is heat resistant, impact resistant, pressure resistant.