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
Quartzite is a non-foliated metamorphic rock that forms by the metamorphism of pure quartz Sandstone
Discoverer
Obsius
Unknown
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From quartz + -ite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Glassy
Foliated, Granular
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Blue, Brown, Green, Light Grey, Purple, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Lustrous
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Homes
Exterior Uses
Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Arrowheads, As Dimension Stone, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone
Medical Industry
Surgery
-
Antiquity Uses
Artifacts, Jewellery
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
An Oil and Gas Reservoir, As armour rock for sea walls, Cemetery Markers, Commemorative Tablets, In aquifers, Laboratory bench tops, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones, Used in aquariums
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Orthoquartzite and Metaquartzite
Features
Blocks negativity, Helps to protect against depression
Generally rough to touch, Is one of the oldest rock
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.
Quartzite forms from sandstone and the mineral quartz being put under extreme heat and pressure.
Mineral Content
-
Chlorite, Epidote, Hematite, Kyanite, Magnetite, Muscovite or Illite, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
-
Medium Grained
Fracture
Conchoidal
Uneven, Splintery or Conchoidal
Porosity
Very Less Porous
Less Porous
Specific Gravity
2.6-2.7
2.6-2.8
Transparency
Translucent
Transparent to Translucent
Density
2.6 g/cm3
2.32-2.42 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, Israel, Russia, South Korea, Thailand, Turkey
Africa
Kenya
Ethiopia, Morocco, South Africa, Zimbabwe
Europe
Greece, Hungary, Iceland, Italy, Turkey
England, Italy, Norway, Scotland, Sweden, United Kingdom
Deposits in Western Continents
North America
Canada, Mexico, USA
Bahamas, Canada, USA
South America
Argentina, Chile, Ecuador, Peru
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand
New Zealand, Queensland, Western Australia
Obsidian vs Quartzite 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 Quartzite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Quartzite. Learn more about Obsidian vs Quartzite in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Quartzite include Countertops, Decorative aggregates, Flooring and Homes. Due to some exceptional properties of Obsidian and Quartzite, 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 Quartzite include Arrowheads, As dimension stone, Cement manufacture, Construction aggregate, Cutting tool, For road aggregate, Making natural cement, Production of glass and ceramics, Rail track ballast, Roadstone.
More about Obsidian and Quartzite
Here you can know more about Obsidian and Quartzite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Quartzite consists of mineral content and compound content. The mineral content of Obsidian includes and mineral content of Quartzite includes Chlorite, Epidote, Hematite, Kyanite, Magnetite, Muscovite or Illite, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Quartzite, 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, Quartzite is available in black, blue, brown, green, light grey, purple, white, yellow colors. Appearance of Obsidian is Shiny and that of Quartzite is Lustrous. Properties of rock is another aspect for Obsidian vs Quartzite. The hardness of Obsidian is 5-5.5 and that of Quartzite is 6-7. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Quartzite are Orthoquartzite and Metaquartzite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Obsidian and Quartzite is white. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Quartzite is 0.75 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 Quartzite is heat resistant, impact resistant, pressure resistant, wear resistant.