Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
North America
USA, Australia
Discoverer
Ferdinand von Richthofen
Tornebohm
Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic, Glassy, Porphyritic
Earthy, Mud-rich, Rough
Color
Grey, White, Light Black
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Gemstone, Laboratory bench tops, Jewelry
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Endoskarns
Features
Acidic in nature, Available in lots of colors
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
-
Grain Size
Large and Coarse Grained
Fine Grained
Fracture
Sub-conchoidal
Irregular
Streak
-
Light to dark brown
Porosity
Highly Porous
Less Porous
Luster
Earthy
Waxy and Dull
Specific Gravity
2.65-2.67
2.86
Transparency
Opaque
Opaque
Density
2.4-2.6 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
South Africa, Western Africa
Europe
Germany, Iceland, Ireland, Italy, Spain
United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, Queensland, Western Australia
Central Australia, Western Australia
All about Rhyolite and Skarn Properties
Know all about Rhyolite and Skarn properties here. All properties of rocks are important as they define the type of rock and its application. Rhyolite belongs to Igneous Rocks while Skarn belongs to Metamorphic Rocks.Texture of Rhyolite is Aphanitic, Glassy, Porphyritic whereas that of Skarn is Earthy, Mud-rich, Rough. Rhyolite appears Banded and Skarn appears Dull. The luster of Rhyolite is earthy while that of Skarn is waxy and dull. Rhyolite is available in grey, white, light black colors whereas Skarn is available in black, brown, green, grey, white colors. The commercial uses of Rhyolite are gemstone, laboratory bench tops, jewelry and that of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo).