Obsidian

Oolite

Obsidian and Oolite

Obsidian

Oolite

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Definition

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

Oolite is a sedimentary rock formed from ooids, spherical grains which are composed of concentric layers of calcite

History

Origin

Ethiopia

Discoverer

Obsius

William Smith

Etymology

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

From oo- + -lite, after German Oolit. A rock consisting of fine grains of carbonate of lime

Class

Igneous Rocks

Sedimentary Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Other Categories

Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Glassy

Clastic or Non-Clastic

Color

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

Black, Blue, Brown, Cream, Green, Grey, Pink, Red, Silver, White, Yellow

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Shiny

Rounded and Rough

Uses

Architecture

Interior Uses

Decorative Aggregates, Interior Decoration

Decorative Aggregates, Flooring, Interior Decoration

Exterior Uses

Garden Decoration

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

Other Architectural Uses

Industry

Construction Industry

Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points

Cement Manufacture, Cobblestones, Landscaping

Medical Industry

Surgery

Antiquity Uses

Artifacts, Jewellery

Artifacts

Other Uses

Commercial Uses

Creating Artwork, Mirror, Used in aquariums

Creating Artwork, Jewelry, Used in aquariums

Types

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

Pisolitic Oolite and Oncolitic Oolite

Features

Blocks negativity, Helps to protect against depression

Available in lots of colors, Generally rough to touch, Very fine grained rock

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Present

Formation

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.

Oolites form when layers of calcite are deposited around a sand grain or fossil piece and are rolled around in calm water, which makes them round.

Composition

Mineral Content

Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt

Compound Content

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

Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, FeO, MgO

Transformation

Metamorphism

✔ ✘

Types of 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

Chemical Erosion, Coastal Erosion

Properties

Physical Properties

Hardness

5-5.53-4

1 7

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Grain Size

Fine Grained

Fracture

Conchoidal

Streak

White

Porosity

Very Less Porous

Less Porous

Luster

Vitreous

Pearly to Shiny

Compressive Strength

0.15 N/mm²40.00 N/mm²

0.15 450

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Cleavage

Toughness

Specific Gravity

2.6-2.7-9999

0 8.4

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Transparency

Translucent

Opaque

Density

2.6 g/cm³-9999 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.92 kJ/Kg K0.65 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant

Heat Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

Afghanistan, Indonesia, Japan, Russia

Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam

Africa

Kenya

Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe

Europe

Greece, Hungary, Iceland, Italy, Turkey

United Kingdom

Others

Deposits in Western Continents

North America

Canada, Mexico, USA

USA

South America

Argentina, Chile, Ecuador, Peru

Colombia

Deposits in Oceania Continent

Australia

New Zealand

Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula

All about Obsidian and Oolite Properties

Know all about Obsidian and Oolite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian belongs to Igneous Rocks while Oolite belongs to Sedimentary Rocks.Texture of Obsidian is Glassy whereas that of Oolite is Clastic or Non-Clastic. Obsidian appears Shiny and Oolite appears Rounded and Rough. The luster of Obsidian is vitreous while that of Oolite is pearly to shiny. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Oolite is available in black, blue, brown, cream, green, grey, pink, red, silver, white, yellow colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Oolite are creating artwork, jewelry, used in aquariums.