Definition
Diorite is a grey to dark-grey intermediate intrusive igneous rock composed principally of plagioclase feldspar,biotite, hornblende, and pyroxene
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 early 19th century coined in French, formed irregularly from Greek diorizein distinguish
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Opaque Rock
Texture
Phaneritic
Glassy
Color
Black, Brown, Light to Dark Grey, White
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
Garden Decoration
Other Architectural Uses
Curbing
-
Construction Industry
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Medical Industry
-
Surgery
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Jewellery
Commercial Uses
Creating Artwork, Curling
Creating Artwork, Mirror, Used in aquariums
Types
Plagioclase Diorite and Quartz Diorite
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Features
Typically speckled black and white.
Blocks negativity, Helps to protect against depression
Archaeological Significance
Formation
Diorite is a coarse-grained intrusive igneous rock which contains large interlocking and randomly oriented crystals and forms when molten lava does not reach the Earth’s surface and cools down in the Earth’s crust.
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, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Muscovite or Illite, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
-
Compound Content
Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
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, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Coarse Grained
-
Streak
Bluish Black
White
Porosity
Very Less Porous
Very Less Porous
Specific Gravity
2.8-3
2.6-2.7
Transparency
Opaque
Translucent
Density
2.8-3 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
-
Afghanistan, Indonesia, Japan, Russia
Europe
Finland, Germany, Italy, Romania, Sweden, Turkey, United Kingdom
Greece, Hungary, Iceland, Italy, Turkey
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New Zealand
All about Diorite and Obsidian Properties
Know all about Diorite and Obsidian properties here. All properties of rocks are important as they define the type of rock and its application. Diorite and Obsidian belong to Igneous Rocks.Texture of Diorite is Phaneritic whereas that of Obsidian is Glassy. Diorite appears Shiny and Obsidian appears Shiny. The luster of Diorite is shiny while that of Obsidian is vitreous. Diorite is available in black, brown, light to dark grey, white colors whereas Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. The commercial uses of Diorite are creating artwork, curling and that of Obsidian are creating artwork, mirror, used in aquariums.