Porphyry

Slate

Porphyry vs Slate

Porphyry

Slate

Add ⊕

Definition

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

Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism

History

Origin

Egypt

England

Discoverer

Unknown

Abraham Gottlob Werner

Etymology

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

From Old French esclate, from esclat (French éclat)

Class

Igneous Rocks

Metamorphic Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Medium Hardness Rock

Family

Group

Plutonic

Other Categories

Fine Grained Rock, Opaque Rock

Texture

Porphyritic

Foliated

Color

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

Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull

Uses

Architecture

Interior Uses

Decorative Aggregates, Interior Decoration

Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads

Exterior Uses

Garden Decoration, Paving Stone

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

Other Architectural Uses

Curbing

Industry

Construction Industry

Construction Aggregate

As Dimension Stone

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts, Monuments, Sculpture, Small Figurines

Other Uses

Commercial Uses

Creating Artwork, Gemstone, Jewelry

Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates

Types

Rhomb Porphyry

Phyllite, Schist, and Slate

Features

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

Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

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.

Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.

Composition

Mineral Content

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

Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon

Compound Content

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

Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion

Properties

Physical Properties

Hardness

6-73-4

1 7

👆🏻

Grain Size

Fine Grained

Very fine-grained

Fracture

Irregular

Splintery

Streak

White

Light to dark brown

Porosity

Less Porous

Luster

Dull

Compressive Strength

150.00 N/mm²30.00 N/mm²

0.15 450

👆🏻

Cleavage

Slaty

Toughness

1.7

1.2

Specific Gravity

2.5-42.65-2.8

0 8.4

👆🏻

Transparency

Translucent to Opaque

Opaque

Density

2.5-2.52 g/cm³2.6-2.8 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.71 kJ/Kg K0.76 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Impact Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

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

China, India, Turkey

Africa

Egypt, Ethiopia, Ghana, South Africa

Europe

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

Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom

Others

Greenland

Arctic

Deposits in Western Continents

North America

Canada, Cuba, Jamaica, USA

USA

South America

Bolivia, Brazil, Colombia, Ecuador, Paraguay

Brazil

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Western Australia

Porphyry vs Slate Information

Earth’s outer layer is covered by rocks and these rocks have different physical and chemical properties. As two rocks are not same, it’s fun to compare them. You can also know more about Porphyry and Slate Reserves. Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix. Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. These rocks are composed of many distinct minerals. The process of formation of rocks is different for various rocks. Rocks are quarried from many years for various purposes. You can check out Porphyry vs Slate information and Porphyry vs Slate characteristics in the upcoming sections.

Compare Igneous Rocks » More

Porphyry vs Tonalite

Porphyry vs Syenite

Porphyry vs Dacite

» More Compare Igneous Rocks

Porphyry vs Slate Characteristics

Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Porphyry vs Slate characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Porphyry and Properties of Slate. Learn more about Porphyry vs Slate in the next section. The interior uses of Porphyry include Decorative aggregates and Interior decoration whereas the interior uses of Slate include Bathrooms, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads. Due to some exceptional properties of Porphyry and Slate, they have various applications in construction industry. The uses of Porphyry in construction industry include Construction aggregate and that of Slate include As dimension stone.

More about Porphyry and Slate

Here you can know more about Porphyry and Slate. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Porphyry and Slate consists of mineral content and compound content. The mineral content of Porphyry includes Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica and mineral content of Slate includes Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Porphyry vs Slate, the texture, color and appearance plays an important role in determining the type of rock. Porphyry is available in black, brown, green, grey, red, rust, white colors whereas, Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors. Appearance of Porphyry is Dull and that of Slate is Dull. Properties of rock is another aspect for Porphyry vs Slate. The hardness of Porphyry is 6-7 and that of Slate is 3-4. The types of Porphyry are Rhomb Porphyry whereas types of Slate are Phyllite, Schist, and Slate. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Porphyry is white while that of Slate is light to dark brown. The specific heat capacity of Porphyry is 0.71 kJ/Kg K and that of Slate is 0.76 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Porphyry is heat resistant, impact resistant whereas Slate is heat resistant, impact resistant, pressure resistant, wear resistant.