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
Diabase is a fine-grained igneous rock which is composed mostly of pyroxene and feldspar
Discoverer
Obsius
Christian Leopold von Buch
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From Greek di + base
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Glassy
Aphanitic, Granular
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Dark Grey to Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Vesicular
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration, Kitchens
Exterior Uses
Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Not Yet Used
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Surgery
Not Yet Used
Antiquity Uses
Artifacts, Jewellery
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
An Oil and Gas Reservoir, Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Not Available
Features
Blocks negativity, Helps to protect against depression
Smooth to touch
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Stonehenge in English county of Wiltshire
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
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.
Diabase forms when molten igneous rock is squeezed up into a vertical crack in other rocks, the crack is usually forced apart and the molten rock cools in the space to form a tabular igneous intrusion cutting across the surrounding rocks and is known as a dike.
Mineral Content
Not Available
Augite, Chlorite, Olivine, Plagioclase, Pyroxene, Pyrrhotite, Serpentine
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Not Applicable
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Porosity
Very Less Porous
Highly Porous
Luster
Vitreous
Not Available
Cleavage
Non-Existent
Not Available
Toughness
Not Available
1.6
Specific Gravity
2.6-2.7
2.86-2.87
Transparency
Translucent
Opaque
Density
2.6 g/cm3
2.7-3.3 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
India
Africa
Kenya
South Africa, Tanzania
Europe
Greece, Hungary, Iceland, Italy, Turkey
Germany, Greece, Italy, Scotland, Turkey
Others
Not Yet Found
Antarctica, Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Argentina, Chile, Ecuador, Peru
Argentina, Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand
Central Australia, New Zealand, Queensland, Western Australia
Obsidian vs Diabase 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 Diabase characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Diabase. Learn more about Obsidian vs Diabase in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Diabase include Countertops, Decorative aggregates, Homes, Interior decoration and Kitchens. Due to some exceptional properties of Obsidian and Diabase, 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 Diabase include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate.
More about Obsidian and Diabase
Here you can know more about Obsidian and Diabase. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Diabase consists of mineral content and compound content. The mineral content of Obsidian is not available and mineral content of Diabase includes Augite, Chlorite, Olivine, Plagioclase, Pyroxene, Pyrrhotite, Serpentine. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Diabase, 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, Diabase is available in dark grey to black colors. Appearance of Obsidian is Shiny and that of Diabase is Vesicular. Properties of rock is another aspect for Obsidian vs Diabase. The hardness of Obsidian is 5-5.5 and that of Diabase is 7. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Diabase are Not Available. 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 Diabase is black. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Diabase is Not Available. 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 Diabase is heat resistant, impact resistant, pressure resistant, wear resistant.