Ignimbrite and Hornfels

Ignimbrite

Hornfels

Definition

Ignimbrite is a volcanic rock consisting mainly of pumice fragments, formed by the consolidation of material deposited by pyroclastic flows

Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock

History

Origin

New Zealand

Discoverer

Patrick Marshall

Unknown

Etymology

From Latin ignis fire + imber, imbr- shower of rain, storm cloud + -ite

From German which means hornstone

Class

Igneous Rocks

Metamorphic Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Durable Rock, Soft Rock

Family

Group

Volcanic

Not Applicable

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Aphanitic

Granular, Platy

Color

Beige, Black, Brown, Grey, Pink, White

Brown, Dark Greenish - Grey, Green, Reddish Brown

Maintenance

Less

Durability

Durable

Water Resistant

Yes

Scratch Resistant

Yes

Stain Resistant

Wind Resistant

Yes

Acid Resistant

Appearance

Dull, Vesicular and Foilated

Dull

Uses

Architecture

Interior Uses

Decorative Aggregates, Floor Tiles, Homes, Interior Decoration

Decorative Aggregates, Flooring, Homes, Interior Decoration

Exterior Uses

As Building Stone, Garden Decoration, Office Buildings, Paving Stone

As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

Building houses or walls, Construction Aggregate

for Road Aggregate, Roadstone

Medical Industry

Not Yet Used

Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Monuments

Other Uses

Commercial Uses

Cemetery Markers, Commemorative Tablets, Creating Artwork

Types

Not Available

Biotite hornfels

Features

Always found as volcanic pipes over deep continental crust

Smooth to touch

Archaeological Significance

Monuments

Used

Famous Monuments

Data Not Available

Sculpture

Used

Not Yet Used

Famous Sculptures

Data Not Available

Not Applicable

Pictographs

Used

Petroglyphs

Used

Figurines

Used

Not Yet Used

Fossils

Absent

Formation

Ignimbrites are formed from very poorly sorted mixture of volcanic ash or tuff and pumice lapilli, commonly with scattered lithic fragments.

Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.

Composition

Mineral Content

Apatite, Biotite, Calcite, Chlorite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz

Andalusite

Compound Content

Ca, NaCl

Fe, Mg

Transformation

Metamorphism

Yes

Types of Metamorphism

Burial Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism

Not Applicable

Weathering

Yes

Types of Weathering

Biological Weathering, Chemical Weathering

Biological Weathering

Erosion

Yes

Types of Erosion

Chemical Erosion, Coastal Erosion

Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion

Properties

Physical Properties

Hardness

4-6

2-3

Grain Size

Fine Grained

Fracture

Uneven

Conchoidal

Streak

White

Unknown

Porosity

Highly Porous

Luster

Vitreous to Dull

Shiny

Compressive Strength

243.80 N/mm²

5.80 N/mm²

Cleavage

Not Available

Perfect

Toughness

Not Available

Not Yet Found

Specific Gravity

2.73

3.4-3.9

Transparency

Opaque

Density

1-1.8 g/cm³

0.25-0.30 g/cm³

Thermal Properties

Specific Heat Capacity

0.20 kJ/Kg K

0.84 kJ/Kg K

Resistance

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Impact Resistant, Pressure Resistant

Reserves

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

Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand

Africa

Cameroon, Cape Verde, Chad, Djibouti, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Tanzania, Uganda

Cameroon, East Africa, Tanzania, Western Africa

Europe

France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom

United Kingdom

Others

Antarctica, Hawaii Islands

Not Yet Found

Deposits in Western Continents

North America

Canada, Costa Rica, Panama, USA

Canada, USA

South America

Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador

Bolivia, Brazil, Colombia, Ecuador

Deposits in Oceania Continent

Australia

Central Australia, Western Australia

New South Wales, New Zealand, Queensland, Western Australia

Summary >>

<< Reserves

All about Ignimbrite and Hornfels Properties

Know all about Ignimbrite and Hornfels properties here. All properties of rocks are important as they define the type of rock and its application. Ignimbrite belongs to Igneous Rocks while Hornfels belongs to Metamorphic Rocks.Texture of Ignimbrite is Aphanitic whereas that of Hornfels is Granular, Platy. Ignimbrite appears Dull, Vesicular and Foilated and Hornfels appears Dull. The luster of Ignimbrite is vitreous to dull while that of Hornfels is shiny. Ignimbrite is available in beige, black, brown, grey, pink, white colors whereas Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. The commercial uses of Ignimbrite and Hornfels are cemetery markers, commemorative tablets, creating artwork.