Variolite

Rhyolite

Variolite and Rhyolite

Variolite

Rhyolite

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1 Definition

1.1 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

Rhyolite is a fine-grained igneous rock which is rich in silica

1.2 History

1.2.1 Origin

France

North America

1.2.2 Discoverer

Unknown

Ferdinand von Richthofen

1.3 Etymology

From Latin varius, speckled, variegated

From German Rhyolit, from Greek rhuax lava stream + lithos stone

1.4 Class

Igneous Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Volcanic

1.6 Other Categories

Opaque Rock

Coarse Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Glassy, Massive, Porphyritic, Scoriaceous, Vesicular

Aphanitic, Glassy, Porphyritic

2.2 Color

Black, Brown, Light to Dark Grey

Grey, White, Light Black

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

Dull and Soft

Banded

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Floor Tiles, Flooring, Homes, Hotels, Kitchens

Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens

3.1.2 Exterior Uses

Garden Decoration, Office Buildings

As Building Stone, As Facing Stone, Paving Stone, Office Buildings

3.1.3 Other Architectural Uses

Curbing

Not Yet Used

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone

Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Creating Artwork

Gemstone, Laboratory bench tops, Jewelry

4 Types

4.1 Types

Not Available

Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.

4.2 Features

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

Acidic in nature, Available in lots of colors

4.3 Archaeological Significance

4.3.1 Monuments

Used

Not Yet Used

4.3.2 Famous Monuments

Data Not Available

Not Applicable

4.3.3 Sculpture

Used

Not Yet Used

4.3.4 Famous Sculptures

Data Not Available

Not Applicable

4.3.5 Pictographs

Used

Not Used

4.3.6 Petroglyphs

Used

Not Used

4.3.7 Figurines

Used

Not Yet Used

4.4 Fossils

Absent

5 Formation

5.1 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.

Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.

5.2 Composition

5.2.1 Mineral Content

Olivine, Plagioclase, Pyroxene

Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz

5.2.2 Compound Content

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

Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium

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

Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Not Applicable

Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

66-7

1 7

6.1.2 Grain Size

Not Applicable

Large and Coarse Grained

6.1.3 Fracture

Conchoidal

Sub-conchoidal

6.1.4 Streak

White to Grey

Colorless

6.1.5 Porosity

Less Porous

Highly Porous

6.1.6 Luster

Not Available

Earthy

6.1.7 Compressive Strength

37.50 N/mm²140.00 N/mm²

0.15 450

6.1.8 Cleavage

Not Available

6.1.9 Toughness

2.3

6.1.10 Specific Gravity

2.8-32.65-2.67

0 8.4

6.1.11 Transparency

Opaque

6.1.12 Density

2.9-3.1 g/cm³2.4-2.6 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

0.84 kJ/Kg KNA

0.14 3.2

6.2.2 Resistance

Heat Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

India, Russia

China, India

7.1.2 Africa

South Africa

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

7.1.3 Europe

Iceland

Germany, Iceland, Ireland, Italy, Spain

7.1.4 Others

Not Yet Found

7.2 Deposits in Western Continents

7.2.1 North America

Canada, USA

7.2.2 South America

Brazil

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

7.3 Deposits in Oceania Continent

7.3.1 Australia

Not Yet Found

New Zealand, Queensland, Western Australia

All about Variolite and Rhyolite Properties

Know all about Variolite and Rhyolite properties here. All properties of rocks are important as they define the type of rock and its application. Variolite and Rhyolite belong to Igneous Rocks.Texture of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Rhyolite is Aphanitic, Glassy, Porphyritic. Variolite appears Dull and Soft and Rhyolite appears Banded. The luster of Variolite is not available while that of Rhyolite is earthy. Variolite is available in black, brown, light to dark grey colors whereas Rhyolite is available in grey, white, light black colors. The commercial uses of Variolite are cemetery markers, creating artwork and that of Rhyolite are gemstone, laboratory bench tops, jewelry.