Mylonite

Porphyry

Mylonite and Porphyry

Mylonite

Porphyry

Add ⊕

Definition

Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism

Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix

History

Origin

New Zealand

Egypt

Discoverer

Unknown

Etymology

From Greek mulōn mill + -ite

From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites

Class

Metamorphic Rocks

Igneous Rocks

Sub-Class

Durable Rock, Medium Hardness Rock

Durable Rock, Hard Rock

Family

Group

Plutonic

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Foliated

Porphyritic

Color

Black to Grey

Black, Brown, Green, Grey, Red, Rust, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull, Banded and Foilated

Dull

Uses

Architecture

Interior Uses

Decorative Aggregates, Interior Decoration

Exterior Uses

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

Garden Decoration, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

for Road Aggregate, Landscaping, Roadstone

Construction Aggregate

Medical Industry

Antiquity Uses

Artifacts, Monuments

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Creating Artwork, Gemstone, Jewelry

Types

Blastomylonites, Ultramylonites and Phyllonites

Rhomb Porphyry

Features

Surfaces are often shiny

Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.

Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.

Composition

Mineral Content

Porphyroblasts

Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica

Compound Content

Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide

Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide

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, Chemical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Sea Erosion, Wind Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

3-46-7

1 7

👆🏻

Grain Size

Fine Grained

Fracture

Conchoidal

Irregular

Streak

White

Porosity

Highly Porous

Less Porous

Luster

Shiny

Dull

Compressive Strength

1.28 N/mm²150.00 N/mm²

0.15 450

👆🏻

Cleavage

Conchoidal

Toughness

1.7

Specific Gravity

2.97-3.052.5-4

0 8.4

👆🏻

Transparency

Opaque

Translucent to Opaque

Density

2.6-4.8 g/cm³2.5-2.52 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

1.50 kJ/Kg K0.71 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant, Pressure Resistant

Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Indonesia, Saudi Arabia, South Korea

China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam

Africa

Eritrea, Ethiopia, Ghana, South Africa, Western Africa

Egypt, Ethiopia, Ghana, South Africa

Europe

England, Finland, France, Germany, Great Britain, Greece, United Kingdom

Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland

Others

Greenland

Deposits in Western Continents

North America

USA

Canada, Cuba, Jamaica, USA

South America

Bolivia, Brazil, Colombia, Ecuador, Paraguay

Deposits in Oceania Continent

Australia

Central Australia, Western Australia

New South Wales, New Zealand, Western Australia

All about Mylonite and Porphyry Properties

Know all about Mylonite and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Mylonite belongs to Metamorphic Rocks while Porphyry belongs to Igneous Rocks.Texture of Mylonite is Foliated whereas that of Porphyry is Porphyritic. Mylonite appears Dull, Banded and Foilated and Porphyry appears Dull. The luster of Mylonite is shiny while that of Porphyry is dull. Mylonite is available in black to grey colors whereas Porphyry is available in black, brown, green, grey, red, rust, white colors. The commercial uses of Mylonite and Porphyry are creating artwork, gemstone, jewelry.