Gneiss

Marl

Gneiss and Marl

Gneiss

Marl

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Definition

Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks

Marl is an unconsolidated sedimentary rock consisting of clay and lime

History

Origin

Discoverer

Unknown

William Smith

Etymology

From the Middle High German verb gneist (to spark; so called because the rock glitters)

From Old French marle, from Late Latin marglia

Class

Metamorphic Rocks

Sedimentary Rocks

Sub-Class

Durable Rock, Hard Rock

Durable Rock, Soft Rock

Family

Group

Other Categories

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

Texture

Banded, Foliated, Platy

Earthy

Color

Black, Brown, Pink, Red, White

Beige, Brown, Green, Grey, White

Maintenance

Less

Durability

Durable

Water Resistant

✔ ✘

Scratch Resistant

✔ ✘

Stain Resistant

✔ ✘

Wind Resistant

✔ ✘

Acid Resistant

✔ ✘

Appearance

Foliated

Rough and Dull

Uses

Architecture

Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

Decorative Aggregates, Floor Tiles

Exterior Uses

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

As Building Stone, Roof Tiles

Other Architectural Uses

Curbing

Industry

Construction Industry

As Dimension Stone

Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar

Medical Industry

Antiquity Uses

Artifacts

Artifacts, Jewellery, Sculpture, Small Figurines

Other Uses

Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Creating Artwork, Soil Conditioner

Types

Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.

Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl

Features

Generally rough to touch, Is one of the oldest rock

Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock

Archaeological Significance

Monuments

Famous Monuments

Konark Sun Temple in India, Washington Monument, US

Sculpture

Famous Sculptures

Pictographs

Petroglyphs

Figurines

Fossils

Absent

Present

Formation

Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.

Marl forms when very fine-grained clay particles are deposited in water which settles at the bottom of water bodies and are compacted by overlying sediment; the water squeezes out and hence forming Marl rock.

Composition

Mineral Content

Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon

Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz

Compound Content

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

Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide

Transformation

Metamorphism

✔ ✘

Types of Metamorphism

Impact Metamorphism

Weathering

✔ ✘

Types of Weathering

Biological Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering

Erosion

✔ ✘

Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion

Properties

Physical Properties

Hardness

72-3

1 7

👆🏻

Grain Size

Medium to Coarse Grained

Very fine-grained

Fracture

Irregular

Conchoidal

Streak

White

Porosity

Very Less Porous

Highly Porous

Luster

Dull

Compressive Strength

125.00 N/mm²30.00 N/mm²

0.15 450

👆🏻

Cleavage

Toughness

1.2

2.6

Specific Gravity

2.5-2.72.2-2.8

0 8.4

👆🏻

Transparency

Translucent to Opaque

Opaque

Density

2.6-2.9 g/cm³2.4-2.8 g/cm³

0 1400

👆🏻

Thermal Properties

Specific Heat Capacity

0.70 kJ/Kg K0.80 kJ/Kg K

0.14 3.2

👆🏻

Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat Resistant, Impact Resistant

Reserves

Deposits in Eastern Continents

Asia

China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia

India, Pakistan, Russia

Africa

Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo

Ethiopia, Kenya, Morocco, South Africa

Europe

Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom

Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland

Others

Deposits in Western Continents

North America

Canada, Costa Rica, Cuba, Mexico, Panama, USA

USA

South America

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

Colombia, Ecuador, Peru

Deposits in Oceania Continent

Australia

New South Wales, New Zealand, Queensland, Victoria

New South Wales, Victoria, Western Australia

All about Gneiss and Marl Properties

Know all about Gneiss and Marl properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Marl belongs to Sedimentary Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Marl is Earthy. Gneiss appears Foliated and Marl appears Rough and Dull. The luster of Gneiss and Marl is dull. Gneiss is available in black, brown, pink, red, white colors whereas Marl is available in beige, brown, green, grey, white colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Marl are creating artwork, soil conditioner.