Felsite

Chert

Felsite and Chert

Felsite

Chert

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Definition

Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition

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

History

Origin

Discoverer

Unknown

Etymology

From English feldspar and -ite

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

Class

Igneous Rocks

Sedimentary Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Durable Rock, Hard Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Arborescent Patterned, Vitreous

Banded, Rough

Color

Black, Blue, Brown, Green, Orange, Red, Tan, Yellow

Black, Brown, Green, Grey, Red, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Layered, Banded, Veined and Shiny

Glassy or Pearly

Uses

Architecture

Interior Uses

Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, Homes

Exterior Uses

Paving Stone, Garden Decoration

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

Other Architectural Uses

Curbing

Industry

Construction Industry

Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points

Arrowheads, Construction Aggregate, Cutting Tool, Spear Points

Medical Industry

Surgery

Antiquity Uses

Artifacts

Artifacts, Monuments

Other Uses

Commercial Uses

Mirror, Jewelry

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

Types

Igneous rock

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

Features

Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock

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

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Present

Formation

Felsite 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.

Composition

Mineral Content

Feldspar, Iron Oxides

Quartz, Silicon

Compound Content

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

Silicon Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Glacier Erosion, Water Erosion

Chemical Erosion

Properties

Physical Properties

Hardness

5-5.56.5-7

1 7

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Grain Size

Fine Grained

Very fine-grained

Fracture

Conchoidal

Uneven, Splintery or Conchoidal

Streak

White

Porosity

Very Less Porous

Highly Porous

Luster

Vitreous

Waxy and Dull

Compressive Strength

0.15 N/mm²450.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

1.5

Specific Gravity

2.6-2.72.5-2.8

0 8.4

👆🏻

Transparency

Translucent

Translucent to Opaque

Density

2.6 g/cm³2.7 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.92 kJ/Kg K0.74 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

Afghanistan, Indonesia, Japan, Russia

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

Africa

Kenya

Kenya, Morocco, South Africa, Tanzania

Europe

Greece, Hungary, Iceland, Italy, Turkey

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

Others

Greenland, Mid-Atlantic Ridge

Deposits in Western Continents

North America

Canada, Mexico, USA

South America

Argentina, Chile, Ecuador, Peru

Bolivia, Brazil

Deposits in Oceania Continent

Australia

New Zealand

New South Wales, Queensland, South Australia, Western Australia

All about Felsite and Chert Properties

Know all about Felsite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Felsite belongs to Igneous Rocks while Chert belongs to Sedimentary Rocks.Texture of Felsite is Arborescent Patterned, Vitreous whereas that of Chert is Banded, Rough. Felsite appears Layered, Banded, Veined and Shiny and Chert appears Glassy or Pearly. The luster of Felsite is vitreous while that of Chert is waxy and dull. Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Chert is available in black, brown, green, grey, red, white colors. The commercial uses of Felsite are mirror, jewelry and that of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.