Andesite

Obsidian

Andesite and Obsidian

Andesite

Obsidian

Add ⊕

Definition

Andesite is a dark, fine-grained, brown or greyish intermediate volcanic rock which is a commonly found in lava

Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth

History

Origin

North America

Ethiopia

Discoverer

Theodor von Gümbel

Obsius

Etymology

From Andes mountains, where it is found in abundance

From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Opaque Rock

Texture

Aphanitic to Porphyritic

Glassy

Color

Bluish - Grey, Grey, Pink, Yellow

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

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull and Soft

Shiny

Uses

Architecture

Interior Uses

Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens

Decorative Aggregates, Interior Decoration

Exterior Uses

Office Buildings, Roof Tiles

Garden Decoration

Other Architectural Uses

Curbing

Industry

Construction Industry

Cobblestones, Construction Aggregate, for Road Aggregate

Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points

Medical Industry

Surgery

Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Jewellery

Other Uses

Commercial Uses

Commemorative Tablets, Creating Artwork

Creating Artwork, Mirror, Used in aquariums

Types

Icelandite

Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian

Features

Generally rough to touch, High silica content, Is one of the oldest rock

Blocks negativity, Helps to protect against depression

Archaeological Significance

Monuments

Famous Monuments

Middle of the Earth in Ecuador

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Andesite is a fine-grained igneous rock that forms when the magma is erupted onto the surface and is crystallized quickly.

When the lava is released from volcano, it undergoes a very rapid cooling which freezes the mechanisms of crystallization. The result is a volcanic glass with a uniform smooth texture.

Composition

Mineral Content

Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite, Magnetite, Plagioclase, Pyroxene, Zircon

Compound Content

Silicon Dioxide

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

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

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

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

75-5.5

1 7

👆🏻

Grain Size

Very fine-grained

Fracture

Uneven

Conchoidal

Streak

White

Porosity

Less Porous

Very Less Porous

Luster

Vitreous

Compressive Strength

225.00 N/mm²0.15 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

1.1

Specific Gravity

2.5-2.82.6-2.7

0 8.4

👆🏻

Transparency

Opaque

Translucent

Density

2.11-2.36 g/cm³2.6 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

2.39 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Indonesia, Japan, Nepal, South Korea

Afghanistan, Indonesia, Japan, Russia

Africa

Egypt, Ethiopia, Morocco, Namibia, South Africa, Tanzania

Kenya

Europe

Austria, Finland, Germany, Italy, Romania, Turkey, United Kingdom

Greece, Hungary, Iceland, Italy, Turkey

Others

Deposits in Western Continents

North America

Mexico, USA

Canada, Mexico, USA

South America

Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela

Argentina, Chile, Ecuador, Peru

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Western Australia

New Zealand

All about Andesite and Obsidian Properties

Know all about Andesite and Obsidian properties here. All properties of rocks are important as they define the type of rock and its application. Andesite and Obsidian belong to Igneous Rocks.Texture of Andesite is Aphanitic to Porphyritic whereas that of Obsidian is Glassy. Andesite appears Dull and Soft and Obsidian appears Shiny. The luster of Andesite and Obsidian is vitreous. Andesite is available in bluish - grey, grey, pink, yellow colors whereas Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. The commercial uses of Andesite are commemorative tablets, creating artwork and that of Obsidian are creating artwork, mirror, used in aquariums.