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
Breccia is a rock consisting of angular fragments of stones which are cemented by finer calcareous material
Discoverer
Obsius
Unknown
Etymology
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
From Italian, literally gravel, Germanic origin and related to break
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Glassy
Brecciated, Clastic
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Beige, Black, Blue, Brown, Buff, Green, Grey, Orange, Pink, Purple, Red, Rust, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Shiny
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration
Exterior Uses
Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Construction Aggregate, Landscaping, Roadstone
Medical Industry
Surgery
-
Antiquity Uses
Artifacts, Jewellery
Artifacts, Sculpture
Commercial Uses
Creating Artwork, Mirror, Used in aquariums
Creating Artwork, Gemstone, Jewelry
Types
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Collapse Breccia, Fault Breccia, Flow Breccia, Pyroclastic Breccia, Igneous Breccia and Impact Breccia
Features
Blocks negativity, Helps to protect against depression
Available in Lots of Colors and Patterns, Clasts are smooth to touch
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.
Breccia is a clastic sedimentary rock which is composed of broken fragments of minerals or rock which are cemented together by a fine-grained matrix and it forms where broken, angular fragments of rock or mineral debris accumulate.
Mineral Content
-
Calcite, Clay, Feldspar, Phosphates, Quartz, Silica
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, Potassium Oxide, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic 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
Grain Size
-
Medium to Coarse Grained
Fracture
Conchoidal
Uneven
Porosity
Very Less Porous
Less Porous
Luster
Vitreous
Dull to Pearly
Specific Gravity
2.6-2.7
2.86-2.87
Transparency
Translucent
Opaque
Density
2.6 g/cm3
0 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Kazakhstan, Mongolia, Russia, South Korea, Uzbekistan
Africa
Kenya
Namibia, Nigeria, South Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Deposits in Western Continents
North America
Canada, Mexico, USA
Barbados, Canada, Mexico, Panama, USA
South America
Argentina, Chile, Ecuador, Peru
Brazil
Deposits in Oceania Continent
Australia
New Zealand
New South Wales, New Zealand
All about Obsidian and Breccia Properties
Know all about Obsidian and Breccia properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian belongs to Igneous Rocks while Breccia belongs to Sedimentary Rocks.Texture of Obsidian is Glassy whereas that of Breccia is Brecciated, Clastic. Obsidian appears Shiny and Breccia appears Layered, Banded, Veined and Shiny. The luster of Obsidian is vitreous while that of Breccia is dull to pearly. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Breccia is available in beige, black, blue, brown, buff, green, grey, orange, pink, purple, red, rust, white, yellow colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Breccia are creating artwork, gemstone, jewelry.