Websterite

Porphyry

Websterite and Porphyry

Websterite

Porphyry

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Definition

Websterite is ultramafic and ultrabasic rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a special type of pyroxenite.

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

History

Origin

Webster, North Carolina

Egypt

Discoverer

Unknown

Etymology

From the town of Webster located in North Carolina

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

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Plutonic

Other Categories

Coarse Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Clastic, Granular, Phaneritic, Porphyritic

Porphyritic

Color

Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey

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

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

Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Interior Decoration

Decorative Aggregates, Interior Decoration

Exterior Uses

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

Garden Decoration, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

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

Construction Aggregate

Medical Industry

Antiquity Uses

Artifacts

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones

Creating Artwork, Gemstone, Jewelry

Types

Ultramafic rock

Rhomb Porphyry

Features

Generally rough to touch, Is one of the oldest rock

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

Websterite can be formed as cumulates in ultramafic intrusions by accumulation of pyroxene crystals at the base of the lava chamber.

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

Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene

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

Compound Content

Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide

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

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Burial Metamorphism, Impact 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, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

76-7

1 7

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Grain Size

Coarse Grained

Fine Grained

Fracture

Uneven

Irregular

Streak

White, Greenish White or Grey

White

Porosity

Less Porous

Luster

Dull to Vitreous to Submetallic

Dull

Compressive Strength

95.00 N/mm²150.00 N/mm²

0.15 450

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Cleavage

Toughness

1.7

Specific Gravity

3.2-3.52.5-4

0 8.4

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Transparency

Opaque

Translucent to Opaque

Density

3.1-3.6 g/cm³2.5-2.52 g/cm³

0 1400

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Thermal Properties

Specific Heat Capacity

0.79 kJ/Kg K0.71 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Impact Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Russia

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

Africa

South Africa

Egypt, Ethiopia, Ghana, South Africa

Europe

Germany, Greece, Italy, Scotland, Turkey

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

Others

Greenland

Deposits in Western Continents

North America

Canada, USA

Canada, Cuba, Jamaica, USA

South America

Brazil, Colombia, Venezuela

Bolivia, Brazil, Colombia, Ecuador, Paraguay

Deposits in Oceania Continent

Australia

New Zealand, Queensland

New South Wales, New Zealand, Western Australia

All about Websterite and Porphyry Properties

Know all about Websterite and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Websterite and Porphyry belong to Igneous Rocks.Texture of Websterite is Clastic, Granular, Phaneritic, Porphyritic whereas that of Porphyry is Porphyritic. Websterite appears Layered, Banded, Veined and Shiny and Porphyry appears Dull. The luster of Websterite is dull to vitreous to submetallic while that of Porphyry is dull. Websterite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors whereas Porphyry is available in black, brown, green, grey, red, rust, white colors. The commercial uses of Websterite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones and that of Porphyry are creating artwork, gemstone, jewelry.