Variolite

Scoria

Variolite and Scoria

Variolite

Scoria

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Definition

Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance

Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities

History

Origin

France

Discoverer

Unknown

Etymology

From Latin varius, speckled, variegated

From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Medium Hardness Rock

Family

Group

Volcanic

Other Categories

Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Glassy, Massive, Porphyritic, Scoriaceous, Vesicular

Vesicular

Color

Black, Brown, Light to Dark Grey

Black, Brown, Dark Grey to Black, Red

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull and Soft

Glassy and Vesicular

Uses

Architecture

Interior Uses

Floor Tiles, Flooring, Homes, Hotels, Kitchens

Decorative Aggregates, Interior Decoration

Exterior Uses

Garden Decoration, Office Buildings

Garden Decoration, Paving Stone

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone

Cement Manufacture, Construction Aggregate, for Road Aggregate, In landscaping and drainage works

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Cemetery Markers, Creating Artwork

As a traction material on snow-covered roads, Creating Artwork, High-temperature insulation, In gas barbecue grills

Types

Metamorphic rock

Basaltic Scoria and Andesitic Scoria

Features

Has High structural resistance against erosion and climate, Very fine grained rock

Available in Lots of Colors and Patterns, Generally rough to touch, Surfaces are often shiny

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.

Scoria forms when magma containing huge amount of dissolved gas flows from a volcano during an eruption.

Composition

Mineral Content

Olivine, Plagioclase, Pyroxene

Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica

Compound Content

Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide

Ca, NaCl

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

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

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

65-6

1 7

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Grain Size

Fine Grained

Fracture

Conchoidal

Streak

White to Grey

White

Porosity

Less Porous

Highly Porous

Luster

Subvitreous to Dull

Compressive Strength

37.50 N/mm²70.00 N/mm²

0.15 450

👆🏻

Cleavage

Perfect

Toughness

2.3

2.1

Specific Gravity

2.8-3-9999

0 8.4

👆🏻

Transparency

Opaque

Density

2.9-3.1 g/cm³-9999 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.84 kJ/Kg K0.84 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Russia

Afghanistan, Indonesia, Japan, Russia

Africa

South Africa

Ethiopia, Kenya, Tanzania

Europe

Iceland

Greece, Hungary, Iceland, Italy, Turkey

Others

Deposits in Western Continents

North America

Canada, USA

Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA

South America

Brazil

Argentina, Chile, Ecuador, Peru

Deposits in Oceania Continent

Australia

New Zealand, Western Australia

All about Variolite and Scoria Properties

Know all about Variolite and Scoria properties here. All properties of rocks are important as they define the type of rock and its application. Variolite and Scoria belong to Igneous Rocks.Texture of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Scoria is Vesicular. Variolite appears Dull and Soft and Scoria appears Glassy and Vesicular. The luster of Variolite is while that of Scoria is subvitreous to dull. Variolite is available in black, brown, light to dark grey colors whereas Scoria is available in black, brown, dark grey to black, red colors. The commercial uses of Variolite are cemetery markers, creating artwork and that of Scoria are as a traction material on snow-covered roads, creating artwork, high-temperature insulation, in gas barbecue grills.