Definition
Ignimbrite is a volcanic rock consisting mainly of pumice fragments, formed by the consolidation of material deposited by pyroclastic flows
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
History
Origin
New Zealand
-
Discoverer
Patrick Marshall
Unknown
Etymology
From Latin ignis fire + imber, imbr- shower of rain, storm cloud + -ite
From the mineral feldspathoid which is the main content of rock
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
Volcanic
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic
Earthy
Color
Beige, Black, Brown, Grey, Pink, White
Black, Brown, Green, Grey, Pink, White
Maintenance
More
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull, Vesicular and Foilated
Dull
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Building houses or walls, Construction Aggregate
As Dimension Stone, Cement Manufacture, for Road Aggregate
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Pyroclastic rock
Igneous rock
Features
Always found as volcanic pipes over deep continental crust
Host Rock for Lead
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
Formation
Ignimbrites are formed from very poorly sorted mixture of volcanic ash or tuff and pumice lapilli, commonly with scattered lithic fragments.
Foidolites 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.
Composition
Mineral Content
Apatite, Biotite, Calcite, Chlorite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz
Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene
Compound Content
Ca, NaCl
Aluminium Oxide, CaO, Iron(III) Oxide, FeO
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion
-
Physical Properties
Hardness
4-61.5
1
7
👆🏻
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Uneven
Conchoidal
Streak
White
White
Porosity
Highly Porous
Very Less Porous
Luster
Vitreous to Dull
Subvitreous to Dull
Compressive Strength
243.80 N/mm280.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
-
-
Specific Gravity
2.732.86
0
8.4
👆🏻
Transparency
Opaque
Translucent
Density
1-1.8 g/cm3-9999 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.20 kJ/Kg K0.79 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Wear 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
Russia
Africa
Cameroon, Cape Verde, Chad, Djibouti, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Tanzania, Uganda
South Africa, Western Africa
Europe
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
-
Others
Antarctica, Hawaii Islands
-
Deposits in Western Continents
North America
Canada, Costa Rica, Panama, USA
Canada, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador
-
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
Central Australia, Western Australia