Picrite

Tuff

Picrite and Tuff

Picrite

Tuff

Add ⊕

Definition

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

Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption

History

Origin

Hawaii Islands

Italy

Discoverer

Unknown

Etymology

From Greek pikros bitter + -ite, 19th century

From a Latin word tophous then in Italian tufo and finally tuff

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Earthy, Rough

Clastic, Pyroclastic

Color

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

Brown, Grey, Yellow

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Rough and Shiny

Dull, Vesicular and Foilated

Uses

Architecture

Interior Uses

Countertops, Decorative Aggregates, Homes, Interior Decoration

Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration

Exterior Uses

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

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

Other Architectural Uses

Curbing

Industry

Construction Industry

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.

Building houses or walls, Construction Aggregate

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts, Monuments, Sculpture, Small Figurines

Other Uses

Commercial Uses

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

Creating Artwork

Types

Oceanite

Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.

Features

Host Rock for Lead

Always found as volcanic pipes over deep continental crust

Archaeological Significance

Monuments

Famous Monuments

Easter Island in the Polynesian Triangle, Pacific Ocean

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

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.

Tuff is formed when large masses of ash and sand which are mixed with hot gases are ejected by a volcano and avalanche rapidly down its slopes.

Composition

Mineral Content

Biotite, Olivine, Plagioclase, Pyrrhotite

Calcite, Chlorite

Compound Content

Al, CaO, Carbon Dioxide, Mg, MgO

Hydrogen Sulfide, Sulfur Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

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

Properties

Physical Properties

Hardness

6.84-6

1 7

👆🏻

Grain Size

Fine Grained

Fracture

Uneven

Streak

White, Greenish White or Grey

White

Porosity

Less Porous

Highly Porous

Luster

Subvitreous to Dull

Vitreous to Dull

Compressive Strength

189.00 N/mm²243.80 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

2.1

Specific Gravity

2.75-2.922.73

0 8.4

👆🏻

Transparency

Opaque

Density

1.5-2.5 g/cm³1-1.8 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.88 kJ/Kg K0.20 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Russia

Afghanistan, Armenia, Azerbaijan, Burma, Cambodia, China, India, Indonesia, Iran, Japan, Malaysia, Mongolia, Nepal, North Korea, Pakistan, Saudi Arabia, Syria, Taiwan, Thailand, Turkey, Vietnam, Yemen

Africa

South Africa

Cameroon, Cape Verde, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Uganda

Europe

Iceland

France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom

Others

Antarctica, Hawaii Islands

Deposits in Western Continents

North America

Canada, USA

Canada, Costa Rica, Panama, USA

South America

Brazil

Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay

Deposits in Oceania Continent

Australia

Central Australia, Western Australia

All about Picrite and Tuff Properties

Know all about Picrite and Tuff properties here. All properties of rocks are important as they define the type of rock and its application. Picrite and Tuff belong to Igneous Rocks.Texture of Picrite is Earthy, Rough whereas that of Tuff is Clastic, Pyroclastic. Picrite appears Rough and Shiny and Tuff appears Dull, Vesicular and Foilated. The luster of Picrite is subvitreous to dull while that of Tuff is vitreous to dull. Picrite and Tuff are available in black, brown, green, grey, pink, white, yellow colors. The commercial uses of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo) and that of Tuff are creating artwork.