Picrite

Pseudotachylite

Picrite and Pseudotachylite

Picrite

Pseudotachylite

Add ⊕

Definition

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

Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.

History

Origin

Hawaii Islands

USA

Discoverer

Unknown

Etymology

From Greek pikros bitter + -ite, 19th century

From pseudo- +‎ tachylite, a glassy rock generated by frictional heat within faults.

Class

Igneous Rocks

Metamorphic Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Earthy, Rough

Quench

Color

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

Black, Brown, Green, Grey, Pink, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Rough and Shiny

Dull and Soft

Uses

Architecture

Interior Uses

Countertops, Decorative Aggregates, Homes, Interior Decoration

Decorative Aggregates, Entryways, Interior Decoration

Exterior Uses

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

As Building Stone, As Facing Stone, Garden Decoration

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.

As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts, Monuments

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, Gemstone

Types

Oceanite

Cataclastic rock

Features

Host Rock for Lead

Archaeological Significance

Monuments

Famous Monuments

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.

Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.

Composition

Mineral Content

Biotite, Olivine, Plagioclase, Pyrrhotite

Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides

Compound Content

Al, CaO, Carbon Dioxide, Mg, MgO

Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering

Erosion

✔ ✘

Types of Erosion

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

Properties

Physical Properties

Hardness

6.87

1 7

👆🏻

Grain Size

Fine Grained

Very fine-grained

Fracture

Uneven

Streak

White, Greenish White or Grey

Light to dark brown

Porosity

Less Porous

Luster

Subvitreous to Dull

Vitreous

Compressive Strength

189.00 N/mm²60.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

2.1

Specific Gravity

2.75-2.922.46-2.86

0 8.4

👆🏻

Transparency

Opaque

Transparent to Translucent

Density

1.5-2.5 g/cm³2.7-2.9 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.88 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Russia

South Korea

Africa

South Africa

Western Africa

Europe

Iceland

Great Britain, Switzerland

Others

Deposits in Western Continents

North America

Canada, USA

South America

Brazil

Deposits in Oceania Continent

Australia

Central Australia, Western Australia

All about Picrite and Pseudotachylite Properties

Know all about Picrite and Pseudotachylite properties here. All properties of rocks are important as they define the type of rock and its application. Picrite belongs to Igneous Rocks while Pseudotachylite belongs to Metamorphic Rocks.Texture of Picrite is Earthy, Rough whereas that of Pseudotachylite is Quench. Picrite appears Rough and Shiny and Pseudotachylite appears Dull and Soft. The luster of Picrite is subvitreous to dull while that of Pseudotachylite is vitreous. Picrite and Pseudotachylite 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 Pseudotachylite are creating artwork, gemstone.