Definition
Ignimbrite is a volcanic rock consisting mainly of pumice fragments, formed by the consolidation of material deposited by pyroclastic flows
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
Discoverer
Patrick Marshall
Unknown
Etymology
From Latin ignis fire + imber, imbr- shower of rain, storm cloud + -ite
From English feldspar and -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic
Arborescent Patterned, Vitreous
Color
Beige, Black, Brown, Grey, Pink, White
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Vesicular and Foilated
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Construction Aggregate
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Medical Industry
-
Surgery
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Mirror, Jewelry
Types
Pyroclastic rock
Igneous rock
Features
Always found as volcanic pipes over deep continental crust
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Archaeological Significance
Formation
Ignimbrites are formed from very poorly sorted mixture of volcanic ash or tuff and pumice lapilli, commonly with scattered lithic fragments.
Felsite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Apatite, Biotite, Calcite, Chlorite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz
Feldspar, Iron Oxides
Compound Content
Ca, NaCl
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Uneven
Conchoidal
Porosity
Highly Porous
Very Less Porous
Luster
Vitreous to Dull
Vitreous
Specific Gravity
2.73
2.6-2.7
Transparency
Opaque
Translucent
Density
1-1.8 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Armenia, Azerbaijan, Burma, Cambodia, China, India, Indonesia, Iran, Japan, Malaysia, Mongolia, Nepal, North Korea, Pakistan, Saudi Arabia, Syria, Taiwan, Thailand, Turkey, Vietnam, Yemen
Afghanistan, Indonesia, Japan, Russia
Africa
Cameroon, Cape Verde, Chad, Djibouti, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Tanzania, Uganda
Kenya
Europe
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
Greece, Hungary, Iceland, Italy, Turkey
Others
Antarctica, Hawaii Islands
-
Deposits in Western Continents
North America
Canada, Costa Rica, Panama, USA
Canada, Mexico, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand
Ignimbrite vs Felsite Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Ignimbrite vs Felsite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Ignimbrite and Properties of Felsite. Learn more about Ignimbrite vs Felsite in the next section. The interior uses of Ignimbrite include Decorative aggregates, Floor tiles, Homes and Interior decoration whereas the interior uses of Felsite include Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Ignimbrite and Felsite, they have various applications in construction industry. The uses of Ignimbrite in construction industry include Building houses or walls, Construction aggregate and that of Felsite include Arrowheads, Cutting tool, Knives, Scrapers, Spear points.
More about Ignimbrite and Felsite
Here you can know more about Ignimbrite and Felsite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Ignimbrite and Felsite consists of mineral content and compound content. The mineral content of Ignimbrite includes Apatite, Biotite, Calcite, Chlorite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz and mineral content of Felsite includes Feldspar, Iron Oxides. You can also check out the list of all Igneous Rocks. When we have to compare Ignimbrite vs Felsite, the texture, color and appearance plays an important role in determining the type of rock. Ignimbrite is available in beige, black, brown, grey, pink, white colors whereas, Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors. Appearance of Ignimbrite is Dull, Vesicular and Foilated and that of Felsite is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Ignimbrite vs Felsite. The hardness of Ignimbrite is 4-6 and that of Felsite is 5-5.5. The types of Ignimbrite are Pyroclastic rock whereas types of Felsite are Igneous rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Ignimbrite and Felsite is white. The specific heat capacity of Ignimbrite is 0.20 kJ/Kg K and that of Felsite is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Ignimbrite is heat resistant, impact resistant, pressure resistant, wear resistant whereas Felsite is heat resistant, impact resistant.