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
Limestone is a sedimentary rock composed mostly of calcite and aragonite, which are different crystal forms of calcium carbonate
Origin
Ethiopia
New Zealand
Discoverer
Obsius
Belsazar Hacquet
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From lime and stone in late 14th Century
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Volcanic
Not Applicable
Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Glassy
Clastic or Non-Clastic
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Beige, Black, Blue, Brown, Cream, Gold, Green, Grey, Light Green, Light Grey, Linen, Pink, Red, Rust, Silver, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Rough and Banded
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Not Yet Used
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Cement Manufacture, Cobblestones, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar, Roadstone, Source of calcium
Medical Industry
Surgery
In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
Antiquity Uses
Artifacts, Jewellery
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
Animal feed filler, As a Feed Additive for Livestock, Paper Industry, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Used in aquariums, Whiting material in toothpaste, paint and paper
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Chalk, Coquina, Fossiliferous Limestone, Lithographic Limestone, Oolitic Limestone, Travertine, Tufa
Features
Blocks negativity, Helps to protect against depression
Host Rock for Lead, Stalactites and stalagmites are formed from this rock, Zinc and Copper Deposits
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Acropolis of Athens in Greece, Agia Sophia in Istanbul, Turkey, Al Aqsa Mosque in Jerusalem, Angkor Wat in Cambodia, Big Ben in London, Charminar in Hyderabad, India, Chhatrapati Shivaji Terminus in Maharashtra, India, Chichen Itza in Mexico, Empire State Building in New York, Khajuraho Temples, India, Kremlin in Moscow, Louvre in Paris, France, Neuschwanstein in Bavaria, Potala Palace in Lahasa, Tibet, Wailing Wall in Jerusalem
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Ajanta Caves in Maharashtra, India, Elephanta Caves in Maharashtra, India
Figurines
Not Yet Used
Used
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.
Limestone is a sedimentary rock which is mainly made up of calcium carbonate.
Mineral Content
Not Available
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, NaCl, CaO, Iron(III) Oxide, FeO, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Not Applicable
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
Grain Size
Not Applicable
Fine Grained
Fracture
Conchoidal
Splintery
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Dull to Pearly
Cleavage
Non-Existent
Non-Existent
Toughness
Not Available
1
Specific Gravity
2.6-2.7
2.3-2.7
Transparency
Translucent
Opaque
Density
2.6 g/cm3
2.3-2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant
Pressure Resistant
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
Not Yet Found
Not Yet Found
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, Tonga, Victoria, Yorke Peninsula
Obsidian vs Limestone 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 Limestone characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Limestone. Learn more about Obsidian vs Limestone in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Limestone include Decorative aggregates and Interior decoration. Due to some exceptional properties of Obsidian and Limestone, 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 Limestone include Cement manufacture, Cobblestones, For road aggregate, Production of glass and ceramics, Raw material for the manufacture of mortar, Roadstone, Source of calcium.
More about Obsidian and Limestone
Here you can know more about Obsidian and Limestone. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Limestone consists of mineral content and compound content. The mineral content of Obsidian is not available and mineral content of Limestone includes Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Limestone, 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, Limestone is available in beige, black, blue, brown, cream, gold, green, grey, light green, light grey, linen, pink, red, rust, silver, white, yellow colors. Appearance of Obsidian is Shiny and that of Limestone is Rough and Banded. Properties of rock is another aspect for Obsidian vs Limestone. The hardness of Obsidian is 5-5.5 and that of Limestone is 3-4. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Limestone are Chalk, Coquina, Fossiliferous Limestone, Lithographic Limestone, Oolitic Limestone, Travertine, Tufa. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Obsidian and Limestone is white. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Limestone is 0.91 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 Limestone is pressure resistant.