Rapakivi Granite

Picrite

Rapakivi Granite and Picrite

Picrite

Add ⊕

Definition

Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase

Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine

History

Origin

Finland, Europe

Hawaii Islands

Discoverer

Jakob Sederholm

Unknown

Etymology

From Finnish Rapakivi which stands for crumbly rock

From Greek pikros bitter + -ite, 19th century

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Plutonic

Volcanic

Other Categories

Coarse Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Granular, Phaneritic

Earthy, Rough

Color

Black, Grey, Orange, Pink, White

Black, Brown, Green, Grey, Pink, White, Yellow

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Veined or Pebbled

Rough and Shiny

Uses

Architecture

Interior Uses

Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads

Countertops, Decorative Aggregates, Homes, Interior Decoration

Exterior Uses

As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts

As Building Stone, As Facing Stone, Garden Decoration, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone

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.

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones

As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)

Types

Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite

Oceanite

Features

Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock

Host Rock for Lead

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks

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.

Composition

Mineral Content

Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz

Biotite, Olivine, Plagioclase, Pyrrhotite

Compound Content

Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide

Al, CaO, Carbon Dioxide, Mg, MgO

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion

Properties

Physical Properties

Hardness

6-76.8

1 7

👆🏻

Grain Size

Large and Coarse Grained

Fine Grained

Fracture

Uneven

Streak

White

White, Greenish White or Grey

Porosity

Less Porous

Luster

Dull to Grainy with Sporadic parts Pearly and Vitreous

Subvitreous to Dull

Compressive Strength

175.00 N/mm²189.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

2.1

Specific Gravity

2.6-2.72.75-2.92

0 8.4

👆🏻

Transparency

Opaque

Density

2.6-2.8 g/cm³1.5-2.5 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.79 kJ/Kg K0.88 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Wear Resistant

Heat Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam

India, Russia

Africa

Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa

South Africa

Europe

Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic

Iceland

Others

Deposits in Western Continents

North America

Canada, USA

South America

Brazil

Deposits in Oceania Continent

Australia

All about Rapakivi Granite and Picrite Properties

Know all about Rapakivi Granite and Picrite properties here. All properties of rocks are important as they define the type of rock and its application. Rapakivi Granite and Picrite belong to Igneous Rocks.Texture of Rapakivi Granite is Granular, Phaneritic whereas that of Picrite is Earthy, Rough. Rapakivi Granite appears Veined or Pebbled and Picrite appears Rough and Shiny. The luster of Rapakivi Granite is dull to grainy with sporadic parts pearly and vitreous while that of Picrite is subvitreous to dull. Rapakivi Granite is available in black, grey, orange, pink, white colors whereas Picrite is available in black, brown, green, grey, pink, white, yellow colors. The commercial uses of Rapakivi Granite are cemetery markers, commemorative tablets, creating artwork, curling, laboratory bench tops, tombstones and that of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo).