Obsidian Rock – Meaning, Uses, Facts, Properties & Color

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Obsidian Rock A Detailed Guide
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Introduction

• We know three main classes of rocks, sedimentary,
  igneous, and metamorphic. In Limestone article,
  we learned how sedimentation occurs, and the
  formation of sedimentary rocks takes place.
  Today, we are going to know Obsidian rock, which
  falls in the main class igneous rocks.
• We know igneous rocks have two basic types.

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1. Intrusive Igneous Rocks

• When molten lava/magma is cooling slowly below
  the surface of the earth and forms large crystals
  in the rocks they known as intrusive igneous
  rocks.

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2 Extrusive Igneous Rocks

• When molten magma is cooling rapidly onto the
  surface of the earth and forms small crystals in
  the rocks they known as extrusive igneous rocks.

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What Is Obsidian Rock?

• Obsidian is a class of igneous rocks, which forms
  when felsic lava extruded from a volcano onto the
  surface of the earth.
• The cooling of lava takes place so rapidly that
  no chance remains for proper crystallization
  (Atomic Arrangements) and finds as an amorphous
  glass material. It has a smooth and uniform
  texture, which breaks with a conchoidal fracture.

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Formation of Obsidian Rocks in Nature

• The obsidian formation can happen in a variety of
  cooling environment such as
• Along the edges of a flow of magma or lava
• Along the edges of a dome of the volcano
• Along the edges of a sill or dike, which takes
  place under the surface and it is the only
  intrusive type
• The point where magma comes into the contact of
  water on the surface
• The point where magma cools due to airborne
  cooling effects

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Properties of Obsidian
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Streaks Colors of Obsidian

• The streak of obsidian is white, but various
  colors occur in nature.
• Frequently found colors of Obsidian rocks are
• The highest occurrence of obsidians is in Black,
  but it also available in Brown, Green, or Tan.
• Rarely found colors of Obsidian rocks are
• A very rare occurrence of obsidians is in Blue,
  Orange, Red, and Yellow.
• The occurrence of color is due to the presence of
  different trace elements in obsidian rocks.

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The hardness of Obsidian (How Hard Is Obsidian
Rocks)

• In physics and geology, the hardness of the
  physical objects or rocks is measured in Mohs
  scale, which rates the objects in question on the
  scale from 1 to 10.
• Rocks with Mohs hardness scale from 1 to 3 are
  considering soft rocks.
• From 3 to 6 scale medium hardness
• From 6 to 10 hardness scale the hardest rocks.
•  It also means obsidian is easy to scratch.

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Compressive Strength of Obsidian

• When a compressive pressure (In Newton unit)
  applied on the rocks a permanent deformation of
  rocks takes place at a point of pressure. It is
  termed as the compressive strength of rocks and
  obsidians fractured or permanently deformed at
  0.15 N per square millimeter. It means obsidian
  is easy to break and chipped by some impacts. It
  also renders obsidian as the unfit stone for
  rings and bracelets like jewelry production.

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Obsidian Fracture

• Obsidians breaks into the conchoidal fracture.
  Obsidian has no natural or defined planes of
  separation when a pressure exceeding from its
  physical strength exerts on it. Therefore,
  smoothly curved fracture takes place on the
  surface of obsidian glass rock.
• The images at the side are depicting the
  phenomena beautifully and precisely.

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Specific Gravity Density of Obsidian

• The density of rock used to expresses as
  specific gravity, and it is measured in relevance
  to the density of water in gram per cubic
  centimeter of the mass. The density of obsidian
  is 2.55 g/cubic cm. It means it is heavier than
  water and dense medium as a mass.

Luster Transparency of Obsidian
In Obsidian, only 1 of water exists. It means it
is vitreous and due to the high presence of
silica and other glass-forming minerals, it is
translucent in transparency.

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What Type of Rock Is Obsidian?
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Mahogany Obsidian
Snowflake Obsidian
Rainbow Obsidian
Gold Sheen Obsidian
Silver Sheen Obsidian
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Purple Sheen Obsidian
Double Flow Obsidian
Black Obsidian
Pumpkin Obsidian
Green Obsidian
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The occurrence of Obsidian Rocks in Different
Geographic Regions of the Earth
Asia Afghanistan, Indonesia, Japan, Armenia, Azerbaijan, and Russia.
Africa Kenya.
Europe Greece, Hungary, Iceland, Italy, Scotland, and Turkey.
North America Canada, Mexico, and USA.
Central America El Salvador, Guatemala, and Papua New Guinea.
South America Argentina, Chile, Ecuador, and Peru.
Australia New Zealand.
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Obsidian Uses
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Obsidians as Weapons Tools

• The human civilization has used obsidian rocks to
  make knives, spear points, arrowheads, scrapers,
  and various weapons.
• Knives and blades were fine for kitchen
  applications. Scrappers were used in land
  digging, agriculture, and gardening applications.
  Arrowheads and spear points were provided the
  sharpest tools for warriors in the creation of
  various weapons.

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Obsidians in Construction Industry

• Obsidian rocks use in interior and exterior
  decoration. Decorative aggregates, gravels, and
  pebbles from obsidian rocks are a favorite
  material for creating architectural beauty and
  artwork on walls, ceilings, and floors of the
  buildings. Artworks in gardens, patios, swimming
  pools, fire features, and water features look
  amazing when obsidian rocks applied along with
  other Gemstones.

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Obsidians in Medical Surgery

• If you look at the sharpest edge of the steel
  blade in the microscope, you will notice almost
  saw-like teeth on edge. Whereas, the obsidian
  blade has no bite because it has evenly sooth
  edge at the microscopic level. Therefore, wounds
  cut by obsidian blades are healing significantly
  faster than wounds by steel blades.
• obsidian can produce the sharpest materials that
  only Nanotechnologies can produce.

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Obsidians in Antiquity and Jewelry Industry

• However, medium strength of obsidian with 5.5
  hardness creates durability concerns and the
  jewelry industry avoid its use as they apply
  diamonds and other gemstones.

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Obsidian Rocks for Sales



Spiderweb
Apache Tears
Cat Eye
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Obsidian Rocks for Sales

Peanut
Flame/Fire
Midnight Lace
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Conclusion

• In the series of identifying various rocks and
  natural stones at World of Stones, USA, we have
  explored different aspects of obsidian rocks such
  as meaning, uses, facts, properties, and colors
  of obsidians.
• World of Stones, USA is an excellent place to buy
  a variety of natural rocks mainly used for
  exterior applications in building construction
  industry. If you are interested to know about
  rocks and stones, keep the reading of blogs at
  World of Stones.

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Thank You

• Contact Us
• https//worldofstonesusa.com/
• info_at_worldofstonesusa.com

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Source

• https//worldofstonesusa.com/blog/obsidian-rock/