Andesite

Variolite

Andesite and Variolite

Andesite

Variolite

Add ⊕

Definition

Andesite is a dark, fine-grained, brown or greyish intermediate volcanic rock which is a commonly found in lava

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

History

Origin

North America

France

Discoverer

Theodor von Gümbel

Unknown

Etymology

From Andes mountains, where it is found in abundance

From Latin varius, speckled, variegated

Class

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Opaque Rock

Texture

Aphanitic to Porphyritic

Glassy, Massive, Porphyritic, Scoriaceous, Vesicular

Color

Bluish - Grey, Grey, Pink, Yellow

Black, Brown, Light to Dark Grey

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull and Soft

Uses

Architecture

Interior Uses

Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens

Floor Tiles, Flooring, Homes, Hotels, Kitchens

Exterior Uses

Office Buildings, Roof Tiles

Garden Decoration, Office Buildings

Other Architectural Uses

Curbing

Industry

Construction Industry

Cobblestones, Construction Aggregate, for Road Aggregate

As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture, Small Figurines

Artifacts, Monuments, Sculpture

Other Uses

Commercial Uses

Commemorative Tablets, Creating Artwork

Cemetery Markers, Creating Artwork

Types

Icelandite

Metamorphic rock

Features

Generally rough to touch, High silica content, Is one of the oldest rock

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

Archaeological Significance

Monuments

Famous Monuments

Middle of the Earth in Ecuador

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Andesite is a fine-grained igneous rock that forms when the magma is erupted onto the surface and is crystallized quickly.

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

Composition

Mineral Content

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

Olivine, Plagioclase, Pyroxene

Compound Content

Silicon Dioxide

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

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Properties

Physical Properties

Hardness

1 7

👆🏻

Grain Size

Very fine-grained

Fracture

Uneven

Conchoidal

Streak

White

White to Grey

Porosity

Less Porous

Luster

Vitreous

Compressive Strength

225.00 N/mm²37.50 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

1.1

2.3

Specific Gravity

2.5-2.82.8-3

0 8.4

👆🏻

Transparency

Opaque

Density

2.11-2.36 g/cm³2.9-3.1 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

2.39 kJ/Kg K0.84 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

India, Indonesia, Japan, Nepal, South Korea

India, Russia

Africa

Egypt, Ethiopia, Morocco, Namibia, South Africa, Tanzania

South Africa

Europe

Austria, Finland, Germany, Italy, Romania, Turkey, United Kingdom

Iceland

Others

Deposits in Western Continents

North America

Mexico, USA

Canada, USA

South America

Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela

Brazil

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Western Australia

All about Andesite and Variolite Properties

Know all about Andesite and Variolite properties here. All properties of rocks are important as they define the type of rock and its application. Andesite and Variolite belong to Igneous Rocks.Texture of Andesite is Aphanitic to Porphyritic whereas that of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Andesite appears Dull and Soft and Variolite appears Dull and Soft. The luster of Andesite is vitreous while that of Variolite is . Andesite is available in bluish - grey, grey, pink, yellow colors whereas Variolite is available in black, brown, light to dark grey colors. The commercial uses of Andesite are commemorative tablets, creating artwork and that of Variolite are cemetery markers, creating artwork.