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
Novaculite is a dense, hard, fine-grained, siliceous metamorpic rock which is a type of chert that breaks with conchoidal fracture
Discoverer
Obsius
Unknown
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From Latin word novacula, for razor stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Glassy
Banded, Glassy, Rough, Vitreous
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Glassy or Pearly
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
Garden Decoration
As Building Stone, Garden Decoration
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Arrowheads, Building houses or walls, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives, Landscaping, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone, Spear Points, Used to sharpen metal tools and weapons
Medical Industry
Surgery
-
Antiquity Uses
Artifacts, Jewellery
Artifacts, Monuments
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
Cemetery Markers, Gemstone, In aquifers, In fire-starting tools, Jewelry, Manufacture of tools, Pebbles are used in ball mills to grind in ceramics industry, To determine the gold content of jewelry
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Sedimentary rock
Features
Blocks negativity, Helps to protect against depression
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
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.
Novaculite forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The formation of Novaculite can be either of chemical or biological origin.
Mineral Content
-
Quartz, Silicon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
-
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Waxy and Dull
Specific Gravity
2.6-2.7
2.5-2.7
Transparency
Translucent
Translucent to Opaque
Density
2.6 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Kenya
Kenya, Morocco, South Africa, Tanzania
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, Mexico, USA
South America
Argentina, Chile, Ecuador, Peru
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New Zealand
New South Wales, Queensland, South Australia, Western Australia
Obsidian vs Novaculite 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 Novaculite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Novaculite. Learn more about Obsidian vs Novaculite in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Novaculite include Countertops, Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Obsidian and Novaculite, 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 Novaculite include Arrowheads, Building houses or walls, Cement manufacture, Construction aggregate, Cutting tool, For road aggregate, Knives, Landscaping, Making natural cement, Production of glass and ceramics, Rail track ballast, Roadstone, Spear points, Used to sharpen metal tools and weapons.
More about Obsidian and Novaculite
Here you can know more about Obsidian and Novaculite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Novaculite consists of mineral content and compound content. The mineral content of Obsidian includes and mineral content of Novaculite includes Quartz, Silicon. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Novaculite, 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, Novaculite is available in black, brown, green, grey, red, white colors. Appearance of Obsidian is Shiny and that of Novaculite is Glassy or Pearly. Properties of rock is another aspect for Obsidian vs Novaculite. The hardness of Obsidian is 5-5.5 and that of Novaculite is 7. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Novaculite are Sedimentary 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 Novaculite is . The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Novaculite is 0.74 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 Novaculite is heat resistant, impact resistant, pressure resistant, wear resistant.