Pegmatite

Hornfels

Pegmatite and Hornfels

Pegmatite

Hornfels

Add ⊕

Definition

Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals

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

R. J. Hauy

Unknown

Etymology

From Greek pegma, pegmat which means- thing joined together + -ite

From German which means hornstone

Class

Igneous Rocks

Metamorphic Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Soft Rock

Family

Group

Plutonic

Other Categories

Coarse Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Pegmatitic

Granular, Platy

Color

Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow

Brown, Dark Greenish - Grey, Green, Reddish Brown

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Layered, Banded, Veined and Shiny

Dull

Uses

Architecture

Interior Uses

Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, Flooring, Homes, Interior Decoration

Exterior Uses

As Building Stone, As Facing Stone, Paving Stone

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

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping

for Road Aggregate, Roadstone

Medical Industry

Antiquity Uses

Artifacts, Sculpture, Small Figurines

Artifacts, Monuments

Other Uses

Commercial Uses

Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz

Cemetery Markers, Commemorative Tablets, Creating Artwork

Types

Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite

Biotite hornfels

Features

Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz

Smooth to touch

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.

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, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz

Andalusite

Compound Content

Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide

Fe, Mg

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

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

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering

Erosion

✔ ✘

Types of Erosion

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

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

Properties

Physical Properties

Hardness

72-3

1 7

👆🏻

Grain Size

Medium to Coarse Grained

Fine Grained

Fracture

Conchoidal

Streak

White

Porosity

Less Porous

Highly Porous

Luster

Grainy, Pearly and Vitreous

Shiny

Compressive Strength

178.54 N/mm²5.80 N/mm²

0.15 450

👆🏻

Cleavage

Perfect

Toughness

2.1

Specific Gravity

2.6-2.633.4-3.9

0 8.4

👆🏻

Transparency

Translucent to Opaque

Opaque

Density

2.6-2.65 g/cm³0.25-0.30 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.79 kJ/Kg K0.84 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant, Pressure Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea

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

Africa

South Africa

Cameroon, East Africa, Tanzania, Western Africa

Europe

Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine

United Kingdom

Others

Deposits in Western Continents

North America

Canada

Canada, USA

South America

Brazil

Bolivia, Brazil, Colombia, Ecuador

Deposits in Oceania Continent

Australia

New South Wales, Queensland, South Australia, Western Australia

New South Wales, New Zealand, Queensland, Western Australia

All about Pegmatite and Hornfels Properties

Know all about Pegmatite and Hornfels properties here. All properties of rocks are important as they define the type of rock and its application. Pegmatite belongs to Igneous Rocks while Hornfels belongs to Metamorphic Rocks.Texture of Pegmatite is Pegmatitic whereas that of Hornfels is Granular, Platy. Pegmatite appears Layered, Banded, Veined and Shiny and Hornfels appears Dull. The luster of Pegmatite is grainy, pearly and vitreous while that of Hornfels is shiny. Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors whereas Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. The commercial uses of Pegmatite are creating artwork, jewelry, source of corundum, tourmalines, beryls and topaz and that of Hornfels are cemetery markers, commemorative tablets, creating artwork.