Picrite

Chert

Picrite and Chert

Picrite

Chert

Add ⊕

1 Definition

1.1 Definition

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

Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture

1.2 History

1.2.1 Origin

Hawaii Islands

Unknown

1.2.2 Discoverer

Unknown

1.3 Etymology

From Greek pikros bitter + -ite, 19th century

From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use

1.4 Class

Igneous Rocks

Sedimentary Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Volcanic

Not Applicable

1.6 Other Categories

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Earthy, Rough

Banded, Rough

2.2 Color

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

Black, Brown, Green, Grey, Red, White

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

2.4.2 Scratch Resistant

✔ ✘

2.4.3 Stain Resistant

✔ ✘

2.4.4 Wind Resistant

✔ ✘

2.4.5 Acid Resistant

✔ ✘

2.5 Appearance

Rough and Shiny

Glassy or Pearly

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Homes, Interior Decoration

Decorative Aggregates, Homes

3.1.2 Exterior Uses

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

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

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 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.

Arrowheads, Construction Aggregate, Cutting Tool, Spear Points

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts, Monuments

3.4 Other Uses

3.4.1 Commercial Uses

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

Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms

4 Types

4.1 Types

Oceanite

Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter

4.2 Features

Host Rock for Lead

Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate

4.3 Archaeological Significance

4.3.1 Monuments

Used

4.3.2 Famous Monuments

Data Not Available

4.3.3 Sculpture

Used

Not Yet Used

4.3.4 Famous Sculptures

Data Not Available

Not Applicable

4.3.5 Pictographs

Not Used

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Used

Not Yet Used

4.4 Fossils

Absent

Present

5 Formation

5.1 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.

Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.

5.2 Composition

5.2.1 Mineral Content

Biotite, Olivine, Plagioclase, Pyrrhotite

Quartz, Silicon

5.2.2 Compound Content

Al, CaO, Carbon Dioxide, Mg, MgO

Silicon Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering

Not Applicable

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

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

Chemical Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6.86.5-7

1 7

6.1.2 Grain Size

Fine Grained

Very fine-grained

6.1.3 Fracture

Uneven

Uneven, Splintery or Conchoidal

6.1.4 Streak

White, Greenish White or Grey

White

6.1.5 Porosity

Less Porous

Highly Porous

6.1.6 Luster

Subvitreous to Dull

Waxy and Dull

6.1.7 Compressive Strength

189.00 N/mm²450.00 N/mm²

0.15 450

6.1.8 Cleavage

Imperfect

Non-Existent

6.1.9 Toughness

2.1

1.5

6.1.10 Specific Gravity

2.75-2.922.5-2.8

0 8.4

6.1.11 Transparency

Opaque

Translucent to Opaque

6.1.12 Density

1.5-2.5 g/cm³2.7 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

0.88 kJ/Kg K0.74 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

India, Russia

China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam

7.1.2 Africa

South Africa

Kenya, Morocco, South Africa, Tanzania

7.1.3 Europe

Iceland

Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom

7.1.4 Others

Not Yet Found

Greenland, Mid-Atlantic Ridge

7.2 Deposits in Western Continents

7.2.1 North America

Canada, USA

Canada, Mexico, USA

7.2.2 South America

Brazil

Bolivia, Brazil

7.3 Deposits in Oceania Continent

7.3.1 Australia

Not Yet Found

New South Wales, Queensland, South Australia, Western Australia

All about Picrite and Chert Properties

Know all about Picrite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Picrite belongs to Igneous Rocks while Chert belongs to Sedimentary Rocks.Texture of Picrite is Earthy, Rough whereas that of Chert is Banded, Rough. Picrite appears Rough and Shiny and Chert appears Glassy or Pearly. The luster of Picrite is subvitreous to dull while that of Chert is waxy and dull. Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors whereas Chert is available in black, brown, green, grey, red, white 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 Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.