Comendite

Chert

Comendite and Chert

Comendite

Chert

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1 Definition

1.1 Definition

Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite

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

Italy

Unknown

1.2.2 Discoverer

Unknown

1.3 Etymology

Comendite derives its name from the area of Le Commende on San Pietro Island in Italy

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

Medium Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Porphyritic

Banded, Rough

2.2 Color

Blue, Bluish - Grey

Black, Brown, Green, Grey, Red, White

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

81% Igneous Rocks Rocks have it !

✔ ✘

59% Sedimentary Rocks Rocks have it !

2.4.2 Scratch Resistant

✔ ✘

86% Igneous Rocks Rocks have it !

✔ ✘

62% Sedimentary Rocks Rocks have it !

2.4.3 Stain Resistant

✔ ✘

66% Igneous Rocks Rocks have it !

✔ ✘

43% Sedimentary Rocks Rocks have it !

2.4.4 Wind Resistant

✔ ✘

49% Igneous Rocks Rocks have it !

✔ ✘

38% Sedimentary Rocks Rocks have it !

2.4.5 Acid Resistant

✔ ✘

48% Igneous Rocks Rocks have it !

✔ ✘

22% Sedimentary Rocks Rocks have it !

2.5 Appearance

Foliated

Glassy or Pearly

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Interior Decoration

Decorative Aggregates, Homes

3.1.2 Exterior Uses

As Building Stone, As Facing Stone, Garden Decoration

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

Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar

Arrowheads, Construction Aggregate, Cutting Tool, Spear Points

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Monuments

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers

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

4 Types

4.1 Types

Rhyolite

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

4.2 Features

Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock

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

Not Yet Used

Used

4.3.2 Famous Monuments

Not Applicable

Data Not Available

4.3.3 Sculpture

Not Yet Used

4.3.4 Famous Sculptures

Not Applicable

4.3.5 Pictographs

Not Used

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Not Yet Used

4.4 Fossils

Absent

Present

5 Formation

5.1 Formation

Comendite is a type of Igneous rock which is formed due to cooling and solidification of lava or magma. It may form 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

Albite, Amphibole, Quartz

Quartz, Silicon

5.2.2 Compound Content

Al, Fe, Potassium Oxide

Silicon Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

97% Igneous Rocks Rocks have it !

✔ ✘

19% Sedimentary Rocks Rocks have it !

5.3.2 Types of Metamorphism

Cataclastic Metamorphism, Regional Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

99% Igneous Rocks Rocks have it !

✔ ✘

78% Sedimentary Rocks Rocks have it !

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Not Applicable

5.3.5 Erosion

✔ ✘

92% Igneous Rocks Rocks have it !

✔ ✘

86% Sedimentary Rocks Rocks have it !

5.3.6 Types of Erosion

Coastal Erosion, Water Erosion

Chemical Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

6-7

6.5-7

6.1.2 Grain Size

Medium Grained

Very fine-grained

6.1.3 Fracture

Pervasive

Uneven, Splintery or Conchoidal

6.1.4 Streak

Bluish Black

White

6.1.5 Porosity

Highly Porous

6.1.6 Luster

Dull

Waxy and Dull

6.1.7 Compressive Strength

What Is Flint

⊕

▶

▼

92.40 N/mm²

Rank: 21 (Overall)▶

450.00 N/mm²

Rank: 1 (Overall)▶

▲

What Is Obsidian

⊕

▶

175 (What Is Grani..)

◀ ▶ ADD ⊕

6.1.8 Cleavage

Not Available

Non-Existent

6.1.9 Toughness

1.5

6.1.10 Specific Gravity

2.38

2.5-2.8

6.1.11 Transparency

Opaque

Translucent to Opaque

6.1.12 Density

Not Available

2.7 g/cm³

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

What Is Banded ..

⊕

▶

▼

Not Available

Rank: N/A (Overall)▶

0.74 kJ/Kg K

Rank: 19 (Overall)▶

▲

What Is Granulite

⊕

▶

1.09 (What Is Trave..)

◀ ▶ ADD ⊕

6.2.2 Resistance

Heat Resistant, Impact Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

China

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

7.1.2 Africa

East Africa

Kenya, Morocco, South Africa, Tanzania

7.1.3 Europe

Italy

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

Not Yet Found

Canada, Mexico, USA

7.2.2 South America

Not Yet Found

Bolivia, Brazil

7.3 Deposits in Oceania Continent

7.3.1 Australia

Queensland

New South Wales, Queensland, South Australia, Western Australia

All about Comendite and Chert Properties

Know all about Comendite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Comendite belongs to Igneous Rocks while Chert belongs to Sedimentary Rocks.Texture of Comendite is Porphyritic whereas that of Chert is Banded, Rough. Comendite appears Foliated and Chert appears Glassy or Pearly. The luster of Comendite is dull while that of Chert is waxy and dull. Comendite is available in blue, bluish - grey colors whereas Chert is available in black, brown, green, grey, red, white colors. The commercial uses of Comendite are cemetery markers and that of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.