Rhyodacite

Porphyry

Rhyodacite and Porphyry

Rhyodacite

Porphyry

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1 Definition

1.1 Definition

Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite

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

1.2 History

1.2.1 Origin

USA

Egypt

1.2.2 Discoverer

Unknown

1.3 Etymology

Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite

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

1.4 Class

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Medium Hardness Rock

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Volcanic

Plutonic

1.6 Other Categories

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Earthy

Porphyritic

2.2 Color

Black to Grey, Dark Greenish - Grey

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

2.3 Maintenance

Less

2.4 Durability

Durable

2.4.1 Water Resistant

✔ ✘

2.4.2 Scratch Resistant

✔ ✘

2.4.3 Stain Resistant

✔ ✘

2.4.4 Wind Resistant

✔ ✘

2.4.5 Acid Resistant

✔ ✘

2.5 Appearance

Skeletal

Dull

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Decorative Aggregates, Interior Decoration

3.1.2 Exterior Uses

As Building Stone, Garden Decoration

Garden Decoration, Paving Stone

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping

Construction Aggregate

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Monuments, Sculpture

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Creating Artwork

Creating Artwork, Gemstone, Jewelry

4 Types

4.1 Types

Not Available

Rhomb Porphyry

4.2 Features

Available in Lots of Colors and Patterns

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

4.3 Archaeological Significance

4.3.1 Monuments

Not Yet Used

Used

4.3.2 Famous Monuments

Not Applicable

Data Not Available

4.3.3 Sculpture

Not Yet Used

Used

4.3.4 Famous Sculptures

Not Applicable

Data Not Available

4.3.5 Pictographs

Used

Not Used

4.3.6 Petroglyphs

Used

Not Used

4.3.7 Figurines

Not Yet Used

Used

4.4 Fossils

Absent

5 Formation

5.1 Formation

Rhyodacite 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.

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.

5.2 Composition

5.2.1 Mineral Content

Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon

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

5.2.2 Compound Content

Ca, Fe, Potassium Oxide, NA, Potassium, Silicon Dioxide

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

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

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

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering, Not Registered

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

5.5-66-7

1 7

6.1.2 Grain Size

Fine Grained

6.1.3 Fracture

Conchoidal

Irregular

6.1.4 Streak

Black

White

6.1.5 Porosity

Less Porous

6.1.6 Luster

Greasy to Dull

Dull

6.1.7 Compressive Strength

200.50 N/mm²NA

0.15 450

6.1.8 Cleavage

Not Available

Imperfect

6.1.9 Toughness

2.1

1.7

6.1.10 Specific Gravity

2.34-2.402.5-4

0 8.4

6.1.11 Transparency

Opaque

Translucent to Opaque

6.1.12 Density

Not Available2.5-2.52 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

1.12 kJ/Kg KNA

0.14 3.2

6.2.2 Resistance

Heat Resistant

Heat Resistant, Impact Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam

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

7.1.2 Africa

Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa

Egypt, Ethiopia, Ghana, South Africa

7.1.3 Europe

Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland

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

7.1.4 Others

Not Yet Found

Greenland

7.2 Deposits in Western Continents

7.2.1 North America

Canada, USA

Canada, Cuba, Jamaica, USA

7.2.2 South America

Not Yet Found

Bolivia, Brazil, Colombia, Ecuador, Paraguay

7.3 Deposits in Oceania Continent

7.3.1 Australia

Not Yet Found

New South Wales, New Zealand, Western Australia

All about Rhyodacite and Porphyry Properties

Know all about Rhyodacite and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Rhyodacite and Porphyry belong to Igneous Rocks.Texture of Rhyodacite is Earthy whereas that of Porphyry is Porphyritic. Rhyodacite appears Skeletal and Porphyry appears Dull. The luster of Rhyodacite is greasy to dull while that of Porphyry is dull. Rhyodacite is available in black to grey, dark greenish - grey colors whereas Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors. The commercial uses of Rhyodacite are cemetery markers, creating artwork and that of Porphyry are creating artwork, gemstone, jewelry.