Obsidian

Rhyodacite

Obsidian vs Rhyodacite

Obsidian

Rhyodacite

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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

Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite

History

Origin

Ethiopia

USA

Discoverer

Obsius

Unknown

Etymology

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

Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite

Class

Igneous Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Other Categories

Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Glassy

Earthy

Color

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

Black to Grey, Dark Greenish - Grey

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Shiny

Skeletal

Uses

Architecture

Interior Uses

Decorative Aggregates, Interior Decoration

Exterior Uses

Garden Decoration

As Building Stone, Garden Decoration

Other Architectural Uses

Curbing

Industry

Construction Industry

Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points

As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping

Medical Industry

Surgery

Antiquity Uses

Artifacts, Jewellery

Artifacts

Other Uses

Commercial Uses

Creating Artwork, Mirror, Used in aquariums

Cemetery Markers, Creating Artwork

Types

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

Intermediate volcanic rock

Features

Blocks negativity, Helps to protect against depression

Available in Lots of Colors and Patterns

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

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.

Rhyodacite 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.

Composition

Mineral Content

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

Compound Content

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

Ca, Fe, Potassium Oxide, Potassium, Silicon Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

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

5-5.55.5-6

1 7

👆🏻

Grain Size

Fine Grained

Fracture

Conchoidal

Streak

White

Black

Porosity

Very Less Porous

Less Porous

Luster

Vitreous

Greasy to Dull

Compressive Strength

0.15 N/mm²200.50 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

2.1

Specific Gravity

2.6-2.72.34-2.40

0 8.4

👆🏻

Transparency

Translucent

Opaque

Density

2.6 g/cm³-9999 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.92 kJ/Kg K1.12 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant

Heat Resistant

Reserves

Deposits in Eastern Continents

Asia

Afghanistan, Indonesia, Japan, Russia

China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam

Africa

Kenya

Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa

Europe

Greece, Hungary, Iceland, Italy, Turkey

Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland

Others

Deposits in Western Continents

North America

Canada, Mexico, USA

Canada, USA

South America

Argentina, Chile, Ecuador, Peru

Deposits in Oceania Continent

Australia

New Zealand

Obsidian vs Rhyodacite Information

Earth’s outer layer is covered by rocks and these rocks have different physical and chemical properties. As two rocks are not same, it’s fun to compare them. You can also know more about Obsidian and Rhyodacite Reserves. 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. Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite. These rocks are composed of many distinct minerals. The process of formation of rocks is different for various rocks. Rocks are quarried from many years for various purposes. You can check out Obsidian vs Rhyodacite information and Obsidian vs Rhyodacite characteristics in the upcoming sections.

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Obsidian vs Rhyodacite Characteristics

Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Obsidian vs Rhyodacite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Rhyodacite. Learn more about Obsidian vs Rhyodacite in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Rhyodacite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Obsidian and Rhyodacite, they have various applications in construction industry. The uses of Obsidian in construction industry include Arrowheads, Cutting tool, Knives, Scrapers, Spear points and that of Rhyodacite include As dimension stone, Construction aggregate, For road aggregate, Landscaping.

More about Obsidian and Rhyodacite

Here you can know more about Obsidian and Rhyodacite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Rhyodacite consists of mineral content and compound content. The mineral content of Obsidian includes and mineral content of Rhyodacite includes Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Rhyodacite, the texture, color and appearance plays an important role in determining the type of rock. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas, Rhyodacite is available in black to grey, dark greenish - grey colors. Appearance of Obsidian is Shiny and that of Rhyodacite is Skeletal. Properties of rock is another aspect for Obsidian vs Rhyodacite. The hardness of Obsidian is 5-5.5 and that of Rhyodacite is 5.5-6. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Rhyodacite are Intermediate volcanic rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Obsidian is white while that of Rhyodacite is black. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Rhyodacite is 1.12 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Obsidian is heat resistant, impact resistant whereas Rhyodacite is heat resistant.