Skarn

Dacite

Skarn and Dacite

Skarn

Dacite

Add ⊕

Definition

Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin

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

History

Origin

USA, Australia

Romania and Moldova, Europe

Discoverer

Tornebohm

Unknown

Etymology

From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.

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

Class

Metamorphic Rocks

Igneous Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Soft Rock

Family

Group

Volcanic

Other Categories

Fine Grained Rock, Opaque Rock

Fine Grained Rock, Medium Grained Rock, Opaque Rock

Texture

Earthy, Mud-rich, Rough

Aphanitic to Porphyritic

Color

Black, Brown, Green, Grey, White

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

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Dull

Vesicular

Uses

Architecture

Interior Uses

Decorative Aggregates, Entryways, Interior Decoration

Exterior Uses

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

As Building Stone, Paving Stone, Garden Decoration

Other Architectural Uses

Curbing

Industry

Construction Industry

As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories

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

Medical Industry

Antiquity Uses

Artifacts, Monuments, Sculpture

Artifacts

Other Uses

Commercial Uses

Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)

Commemorative Tablets, Creating Artwork

Types

Endoskarns

Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite

Features

Host Rock for Lead, Zinc and Copper Deposits

Host Rock for Lead, Is one of the oldest rock

Archaeological Significance

Monuments

Famous Monuments

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Formation

Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.

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.

Composition

Mineral Content

Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite

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

Compound Content

Au, CaO, Carbon Dioxide, Cu, Fe, MgO

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

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

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

Burial Metamorphism, Cataclastic Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion

Properties

Physical Properties

Hardness

6.52-2.25

1 7

👆🏻

Grain Size

Fine Grained

Medium to Fine Coarse Grained

Fracture

Irregular

Conchoidal

Streak

Light to dark brown

White

Porosity

Less Porous

Luster

Waxy and Dull

Subvitreous to Dull

Compressive Strength

70.00 N/mm²70.00 N/mm²

0.15 450

👆🏻

Cleavage

Slaty

Perfect

Toughness

2.4

Specific Gravity

2.862.86-2.87

0 8.4

👆🏻

Transparency

Opaque

Translucent

Density

2.8-2.9 g/cm³2.77-2.771 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.92 kJ/Kg K0.92 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Russia, Saudi Arabia, South Korea, Sri Lanka

Africa

South Africa, Western Africa

Europe

United Kingdom

France, Greece, Romania, Scotland, Spain

Others

Deposits in Western Continents

North America

Canada

USA

South America

Brazil, Colombia, Paraguay

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

Deposits in Oceania Continent

Australia

Central Australia, Western Australia

New Zealand, South Australia, Western Australia

All about Skarn and Dacite Properties

Know all about Skarn and Dacite properties here. All properties of rocks are important as they define the type of rock and its application. Skarn belongs to Metamorphic Rocks while Dacite belongs to Igneous Rocks.Texture of Skarn is Earthy, Mud-rich, Rough whereas that of Dacite is Aphanitic to Porphyritic. Skarn appears Dull and Dacite appears Vesicular. The luster of Skarn is waxy and dull while that of Dacite is subvitreous to dull. Skarn is available in black, brown, green, grey, white colors whereas Dacite is available in bluish - grey, brown, grey, light to dark grey colors. The commercial uses of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo) and that of Dacite are commemorative tablets, creating artwork.