Dacite and Tonalite

Dacite

Tonalite

Definition

Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite

Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture

History

Origin

Romania and Moldova, Europe

Tonale, Italy

Discoverer

Unknown

Etymology

From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described

From Tonale Pass, northern Italy, + -ite1

Class

Igneous Rocks

Sub-Class

Durable Rock, Soft Rock

Durable Rock, Hard Rock

Family

Group

Volcanic

Plutonic

Other Categories

Fine Grained Rock, Medium Grained Rock, Opaque Rock

Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock

Texture

Aphanitic to Porphyritic

Phaneritic

Color

Bluish - Grey, Brown, Grey, Light to Dark Grey

Black, Brown, Light to Dark Grey, White

Maintenance

Less

Durability

Durable

Water Resistant

Yes

Scratch Resistant

Yes

Stain Resistant

Yes

Wind Resistant

Acid Resistant

Yes

Appearance

Vesicular

Banded and Foilated

Uses

Architecture

Interior Uses

Decorative Aggregates, Entryways, Interior Decoration

Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration

Exterior Uses

As Building Stone, Paving Stone, Garden Decoration

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

Other Architectural Uses

Curbing

Industry

Construction Industry

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

As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate

Medical Industry

Not Yet Used

Antiquity Uses

Artifacts

Artifacts, Sculpture

Other Uses

Commercial Uses

Commemorative Tablets, Creating Artwork

Cemetery Markers, Creating Artwork

Types

Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite

Dacite

Features

Host Rock for Lead, Is one of the oldest rock

Is one of the oldest rock, Typically speckled black and white.

Archaeological Significance

Monuments

Not Yet Used

Famous Monuments

Not Applicable

Sculpture

Not Yet Used

Used

Famous Sculptures

Not Applicable

Data Not Available

Pictographs

Used

Not Used

Petroglyphs

Used

Not Used

Figurines

Not Yet Used

Used

Fossils

Absent

Formation

Dacitic magma is formed by the subduction of young oceanic crust under a thick felsic continental plate. Further, the Oceanic crust is hydrothermally altered as quartz and sodium are added.

When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes tonalite with quartz as major mineral.

Composition

Mineral Content

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

Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon

Compound Content

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

NaCl, CaO, MgO, Silicon Dioxide

Transformation

Metamorphism

Yes

Types of Metamorphism

Burial Metamorphism, Cataclastic Metamorphism

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

Weathering

Yes

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

Yes

Types of Erosion

Chemical Erosion

Wind Erosion

Properties

Physical Properties

Hardness

2-2.25

6-7

Grain Size

Medium to Fine Coarse Grained

Fracture

Conchoidal

Streak

White

Bluish Black

Porosity

Less Porous

Very Less Porous

Luster

Subvitreous to Dull

Cleavage

Perfect

Not Available

Toughness

Not Available

2.1

Specific Gravity

2.86-2.87

2.86-3

Transparency

Translucent

Opaque

Density

2.77-2.771 g/cm³

2.73 g/cm³

Thermal Properties

Specific Heat Capacity

0.92 kJ/Kg K

Resistance

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Heat Resistant, Pressure Resistant, Water Resistant

Reserves

Deposits in Eastern Continents

Asia

Not Yet Found

Africa

Not Yet Found

Egypt

Europe

France, Greece, Romania, Scotland, Spain

Finland, Germany, Italy, Romania, Sweden, Turkey

Others

Not Yet Found

Deposits in Western Continents

North America

USA

South America

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

Argentina, Bolivia, Chile, Colombia, Ecuador, Peru

Deposits in Oceania Continent

Australia

New Zealand, South Australia, Western Australia

Summary >>

<< Reserves

All about Dacite and Tonalite Properties

Know all about Dacite and Tonalite properties here. All properties of rocks are important as they define the type of rock and its application. Dacite and Tonalite belong to Igneous Rocks.Texture of Dacite is Aphanitic to Porphyritic whereas that of Tonalite is Phaneritic. Dacite appears Vesicular and Tonalite appears Banded and Foilated. The luster of Dacite and Tonalite is subvitreous to dull. Dacite is available in bluish - grey, brown, grey, light to dark grey colors whereas Tonalite is available in black, brown, light to dark grey, white colors. The commercial uses of Dacite are commemorative tablets, creating artwork and that of Tonalite are cemetery markers, creating artwork.