1 Definition
1.1 Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Novaculite is a dense, hard, fine-grained, siliceous metamorpic rock which is a type of chert that breaks with conchoidal fracture
1.2 History
1.2.1 Origin
1.2.2 Discoverer
Ferdinand von Richthofen
Unknown
1.3 Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
From Latin word novacula, for razor stone
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Aphanitic, Glassy, Porphyritic
Banded, Glassy, Rough, Vitreous
2.2 Color
Grey, White, Light Black
Black, Brown, Green, Grey, Red, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Countertops, Decorative Aggregates, Flooring, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
As Building Stone, Garden Decoration
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
Arrowheads, Building houses or walls, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives, Landscaping, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone, Spear Points, Used to sharpen metal tools and weapons
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts
Artifacts, Monuments
3.4 Other Uses
3.4.1 Commercial Uses
Gemstone, Laboratory bench tops, Jewelry
Cemetery Markers, Gemstone, In aquifers, In fire-starting tools, Jewelry, Manufacture of tools, Pebbles are used in ball mills to grind in ceramics industry, To determine the gold content of jewelry
4 Types
4.1 Types
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Not Available
4.2 Features
Acidic in nature, Available in lots of colors
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Not Applicable
Data Not Available
4.3.3 Sculpture
Not Yet Used
Not Yet Used
4.3.4 Famous Sculptures
Not Applicable
Not Applicable
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
Not Yet Used
Not Yet Used
4.4 Fossils
5 Formation
5.1 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.
Novaculite forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The formation of Novaculite can be either of chemical or biological origin.
5.2 Composition
5.2.1 Mineral Content
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Quartz, Silicon
5.2.2 Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Ca, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Not Applicable
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Large and Coarse Grained
Fine Grained
6.1.3 Fracture
Sub-conchoidal
Conchoidal
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Less Porous
6.1.6 Luster
6.1.7 Compressive Strength
140.00 N/mm2450.00 N/mm2
0.15
450
6.1.8 Cleavage
Not Available
Non-Existent
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
Opaque
Translucent to Opaque
6.1.12 Density
2.4-2.6 g/cm32.7 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
China, India
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
7.1.2 Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Kenya, Morocco, South Africa, Tanzania
7.1.3 Europe
Germany, Iceland, Ireland, Italy, Spain
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
7.1.4 Others
Not Yet Found
Greenland, Mid-Atlantic Ridge
7.2 Deposits in Western Continents
7.2.1 North America
Canada, USA
Canada, Mexico, USA
7.2.2 South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Bolivia, Brazil
7.3 Deposits in Oceania Continent
7.3.1 Australia
New Zealand, Queensland, Western Australia
New South Wales, Queensland, South Australia, Western Australia