Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
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
Discoverer
Unknown
Obsius
Etymology
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
Texture
Clastic, Splintery
Glassy
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
Garden Decoration
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Medical Industry
Not Yet Used
Surgery
Antiquity Uses
Artifacts, Sculpture
Artifacts, Jewellery
Commercial Uses
Creating Artwork, Pottery
Creating Artwork, Mirror, Used in aquariums
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Blocks negativity, Helps to protect against depression
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Jantar Mantar in India
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
Formation
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
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.
Mineral Content
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Not Available
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact 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, Glacier Erosion
Grain Size
Very fine-grained
Not Applicable
Fracture
Not Available
Conchoidal
Porosity
Highly Porous
Very Less Porous
Cleavage
Slaty
Non-Existent
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
2.6-2.7
Transparency
Opaque
Translucent
Density
2.4-2.8 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
Afghanistan, Indonesia, Japan, Russia
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Kenya
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Greece, Hungary, Iceland, Italy, Turkey
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
New Zealand
Shale vs Obsidian 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. Shale vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Shale and Properties of Obsidian. Learn more about Shale vs Obsidian in the next section. The interior uses of Shale include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration. Due to some exceptional properties of Shale and Obsidian, they have various applications in construction industry. The uses of Shale in construction industry include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Shale and Obsidian
Here you can know more about Shale and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Shale and Obsidian consists of mineral content and compound content. The mineral content of Shale includes Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides and mineral content of Obsidian is not available. You can also check out the list of all Sedimentary Rocks. When we have to compare Shale vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Shale is available in black, brown, buff, green, grey, red, yellow colors whereas, Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Shale is Muddy and that of Obsidian is Shiny. Properties of rock is another aspect for Shale vs Obsidian. The hardness of Shale is 3 and that of Obsidian is 5-5.5. The types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale whereas types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Shale and Obsidian is white. The specific heat capacity of Shale is 0.39 kJ/Kg K and that of Obsidian 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.Shale is heat resistant, impact resistant whereas Obsidian is heat resistant, impact resistant.
