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
  
Marl is an unconsolidated sedimentary rock consisting of clay and lime
  
History
  
  
Origin
Ethiopia
  
Unknown
  
Discoverer
Obsius
  
Unknown
  
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
  
From Old French marle, from Late Latin marglia
  
Class
Igneous Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Soft Rock
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
Other Categories
Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Glassy
  
Earthy
  
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
  
Beige, Brown, Green, Grey, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Shiny
  
Rough and Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Floor Tiles
  
Exterior Uses
Garden Decoration
  
As Building Stone, Roof Tiles
  
Other Architectural Uses
Not Yet Used
  
Curbing
  
Industry
  
  
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Surgery
  
Not Yet Used
  
Antiquity Uses
Artifacts, Jewellery
  
Artifacts, Jewellery, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
  
Creating Artwork, Soil Conditioner
  
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
  
Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl
  
Features
Blocks negativity, Helps to protect against depression
  
Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Not Yet Used
  
Famous Monuments
Not Applicable
  
Not Applicable
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Present
  
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.
  
Marl forms when very fine-grained clay particles are deposited in water which settles at the bottom of water bodies and are compacted by overlying sediment; the water squeezes out and hence forming Marl rock.
  
Composition
  
  
Mineral Content
Not Available
  
Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz
  
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, Silicon Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
5-5.5
  
2-3
  
Grain Size
Not Applicable
  
Very fine-grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Highly Porous
  
Luster
Vitreous
  
Dull
  
Compressive Strength
Not Available
  
Cleavage
Non-Existent
  
Not Available
  
Toughness
Not Available
  
2.6
  
Specific Gravity
2.6-2.7
  
2.2-2.8
  
Transparency
Translucent
  
Opaque
  
Density
2.6 g/cm3
  
2.4-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
Not Available
  
Resistance
Heat Resistant, Impact Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
Afghanistan, Indonesia, Japan, Russia
  
India, Pakistan, Russia
  
Africa
Kenya
  
Ethiopia, Kenya, Morocco, South Africa
  
Europe
Greece, Hungary, Iceland, Italy, Turkey
  
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, Mexico, USA
  
USA
  
South America
Argentina, Chile, Ecuador, Peru
  
Colombia, Ecuador, Peru
  
Deposits in Oceania Continent
  
  
Australia
New Zealand
  
New South Wales, Victoria, Western Australia
  
Obsidian vs Marl 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 Marl characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Obsidian and Properties of Marl. Learn more about Obsidian vs Marl in the next section. The interior uses of Obsidian include Decorative aggregates and Interior decoration whereas the interior uses of Marl include Decorative aggregates and Floor tiles. Due to some exceptional properties of Obsidian and Marl, 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 Marl include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Obsidian and Marl
Here you can know more about Obsidian and Marl. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Obsidian and Marl consists of mineral content and compound content. The mineral content of Obsidian is not available and mineral content of Marl includes Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Obsidian vs Marl, 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, Marl is available in beige, brown, green, grey, white colors. Appearance of Obsidian is Shiny and that of Marl is Rough and Dull. Properties of rock is another aspect for Obsidian vs Marl. The hardness of Obsidian is 5-5.5 and that of Marl is 2-3. The types of Obsidian are Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian whereas types of Marl are Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Obsidian and Marl is white. The specific heat capacity of Obsidian is 0.92 kJ/Kg K and that of Marl 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 Marl is heat resistant, impact resistant.