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
Dolomite is a sedimentary rock containing more than 50 percent of the mineral dolomite by weight
Origin
Ethiopia
Southern Alps, France
Discoverer
Obsius
Dolomieu
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From French, from the name of Dolomieu (1750–1801), the French geologist who discovered the rock
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Glassy or Pearly
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Garden Decoration
Garden Decoration, Office Buildings
Other Architectural Uses
-
-
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics, Serves as an Oil and Gas Reservoir rock
Medical Industry
Surgery
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Jewellery
Artifacts, Jewellery, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Boninite and Jasperoid
Features
Blocks negativity, Helps to protect against depression
Host Rock for Lead, Traps for subsurface fluids like Oil and Natural Gas., Zinc and Copper Deposits
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.
Dolomite rocks are originally deposited as calcite or aragonite rich limestone, but during diagenesis process, the calcite or aragonite is transformed into dolomite.
Mineral Content
-
Clay Minerals, Pyrite, Quartz, Sulfides
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact 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
-
Grain Size
-
Medium to Fine Coarse Grained
Fracture
Conchoidal
Conchoidal
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Vitreous and Pearly
Specific Gravity
2.6-2.7
2.8-3
Transparency
Translucent
Transparent to Translucent
Density
2.6 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India
Africa
Kenya
Morocco, Namibia
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, Italy, Romania, Spain, Switzerland
Deposits in Western Continents
North America
Canada, Mexico, USA
Mexico, USA
South America
Argentina, Chile, Ecuador, Peru
Brazil, Colombia
Deposits in Oceania Continent
Australia
New Zealand
New South Wales, Queensland, Yorke Peninsula
Obsidian vs Dolomite 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 Dolomite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Dolomite. Learn more about Obsidian vs Dolomite in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Dolomite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Obsidian and Dolomite, 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 Dolomite include As a flux in the production of steel and pig iron, As a sintering agent in steel industry to process iron ore, As dimension stone, Cement manufacture, For road aggregate, Making natural cement, Manufacture of magnesium and dolomite refractories, Production of glass and ceramics, Serves as an oil and gas reservoir rock.
More about Obsidian and Dolomite
Here you can know more about Obsidian and Dolomite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Dolomite consists of mineral content and compound content. The mineral content of Obsidian includes and mineral content of Dolomite includes Clay Minerals, Pyrite, Quartz, Sulfides. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Dolomite, 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, Dolomite is available in black, brown, green, grey, pink, white colors. Appearance of Obsidian is Shiny and that of Dolomite is Glassy or Pearly. Properties of rock is another aspect for Obsidian vs Dolomite. The hardness of Obsidian is 5-5.5 and that of Dolomite is 3.5-4. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Dolomite are Boninite and Jasperoid. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Obsidian and Dolomite is white. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Dolomite is 0.92 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 Dolomite is heat resistant, pressure resistant, wear resistant.