Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Texture
Color
Maintenance
Durability
Water Resistant
Scratch Resistant
Stain Resistant
Wind Resistant
Acid Resistant
Appearance
Interior Uses
Exterior Uses
Other Architectural Uses
Construction Industry
Medical Industry
Antiquity Uses
Commercial Uses
Types
Features
Monuments
Famous Monuments
Sculpture
Famous Sculptures
Pictographs
Petroglyphs
Figurines
Fossils
Formation
Mineral Content
Compound Content
Metamorphism
Types of Metamorphism
Weathering
Types of Weathering
Erosion
Types of Erosion
Hardness
Grain Size
Fracture
Streak
Porosity
Luster
Compressive Strength
Cleavage
Toughness
Specific Gravity
Transparency
Density
Specific Heat Capacity
Resistance
Asia
Africa
Europe
Others
North America
South America
Australia
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
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
Durable Rock, Medium Hardness Rock
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Decorative Aggregates, Interior Decoration
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Creating Artwork, Mirror, Used in aquariums
Fireworks Obsidian, Mahogany, Sheen Obsidian, Snowflake obsidian and Velvet Peacock Obsidian
Blocks negativity, Helps to protect against depression
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.
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Erosion, Coastal Erosion, Glacier Erosion
Heat Resistant, Impact Resistant
Afghanistan, Indonesia, Japan, Russia
Greece, Hungary, Iceland, Italy, Turkey
Argentina, Chile, Ecuador, Peru
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Fine Grained Rock, Opaque Rock
Decorative Aggregates, Homes, Interior Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, raw material for manufacture of quicklime and slaked lime, Source of calcium
Artifacts, Monuments, Sculpture, Small Figurines
Alumina Refineries, Creating Artwork, Drawing on blackboards, Gymnasts, athletes and mountain climbers use for grip, In aquifers, Paper Industry, Production of Lime, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Whiting, Whiting material in toothpaste, paint and paper
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Calcite, Clay, Clay Minerals, Quartz, Sand
Biological Weathering, Chemical Weathering
Chemical Erosion, Coastal Erosion, Water Erosion
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
England, France, Germany, Spain, United Kingdom
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula