Gneiss

Novaculite

Gneiss and Novaculite

Gneiss

Novaculite

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1 Definition

1.1 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

Novaculite is a dense, hard, fine-grained, siliceous metamorpic rock which is a type of chert that breaks with conchoidal fracture

1.2 History

1.2.1 Origin

Unknown

1.2.2 Discoverer

Unknown

1.3 Etymology

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

From Latin word novacula, for razor stone

1.4 Class

Metamorphic Rocks

Sedimentary Rocks

1.4.1 Sub-Class

Durable Rock, Hard Rock

1.5 Family

1.5.1 Group

Not Applicable

1.6 Other Categories

Coarse Grained Rock, Medium Grained Rock, Opaque Rock

Fine Grained Rock, Opaque Rock

2 Texture

2.1 Texture

Banded, Foliated, Platy

Banded, Glassy, Rough, Vitreous

2.2 Color

Black, Brown, Pink, Red, White

Black, Brown, Green, Grey, Red, White

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

Foliated

Glassy or Pearly

3 Uses

3.1 Architecture

3.1.1 Interior Uses

Countertops, Decorative Aggregates, Flooring, Interior Decoration

3.1.2 Exterior Uses

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

As Building Stone, Garden Decoration

3.1.3 Other Architectural Uses

Curbing

3.2 Industry

3.2.1 Construction Industry

As Dimension Stone

Arrowheads, Building houses or walls, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives, Landscaping, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone, Spear Points, Used to sharpen metal tools and weapons

3.2.2 Medical Industry

Not Yet Used

3.3 Antiquity Uses

Artifacts

Artifacts, Monuments

3.4 Other Uses

3.4.1 Commercial Uses

Cemetery Markers, Jewelry, Tombstones, Used in aquariums

Cemetery Markers, Gemstone, In aquifers, In fire-starting tools, Jewelry, Manufacture of tools, Pebbles are used in ball mills to grind in ceramics industry, To determine the gold content of jewelry

4 Types

4.1 Types

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

Not Available

4.2 Features

Generally rough to touch, Is one of the oldest rock

Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate

4.3 Archaeological Significance

4.3.1 Monuments

Used

4.3.2 Famous Monuments

Konark Sun Temple in India, Washington Monument, US

Data Not Available

4.3.3 Sculpture

Not Yet Used

4.3.4 Famous Sculptures

Not Applicable

4.3.5 Pictographs

Not Used

4.3.6 Petroglyphs

Not Used

4.3.7 Figurines

Not Yet Used

4.4 Fossils

Absent

Present

5 Formation

5.1 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.

Novaculite forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The formation of Novaculite can be either of chemical or biological origin.

5.2 Composition

5.2.1 Mineral Content

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

Quartz, Silicon

5.2.2 Compound Content

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

Ca, Silicon Dioxide

5.3 Transformation

5.3.1 Metamorphism

✔ ✘

5.3.2 Types of Metamorphism

Impact Metamorphism

Not Applicable

5.3.3 Weathering

✔ ✘

5.3.4 Types of Weathering

Biological Weathering, Mechanical Weathering

Not Applicable

5.3.5 Erosion

✔ ✘

5.3.6 Types of Erosion

Chemical Erosion, Coastal Erosion, Sea Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

6 Properties

6.1 Physical Properties

6.1.1 Hardness

1 7

6.1.2 Grain Size

Medium to Coarse Grained

Fine Grained

6.1.3 Fracture

Irregular

Conchoidal

6.1.4 Streak

White

Colorless

6.1.5 Porosity

Very Less Porous

Less Porous

6.1.6 Luster

Dull

Waxy and Dull

6.1.7 Compressive Strength

125.00 N/mm²450.00 N/mm²

0.15 450

6.1.8 Cleavage

Poor

Non-Existent

6.1.9 Toughness

1.2

1.5

6.1.10 Specific Gravity

2.5-2.72.5-2.7

0 8.4

6.1.11 Transparency

Translucent to Opaque

6.1.12 Density

2.6-2.9 g/cm³2.7 g/cm³

0 1400

6.2 Thermal Properties

6.2.1 Specific Heat Capacity

NA0.74 kJ/Kg K

0.14 3.2

6.2.2 Resistance

Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant

Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant

7 Reserves

7.1 Deposits in Eastern Continents

7.1.1 Asia

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

China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam

7.1.2 Africa

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

Kenya, Morocco, South Africa, Tanzania

7.1.3 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, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom

7.1.4 Others

Not Yet Found

Greenland, Mid-Atlantic Ridge

7.2 Deposits in Western Continents

7.2.1 North America

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

Canada, Mexico, USA

7.2.2 South America

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

Bolivia, Brazil

7.3 Deposits in Oceania Continent

7.3.1 Australia

New South Wales, New Zealand, Queensland, Victoria

New South Wales, Queensland, South Australia, Western Australia

All about Gneiss and Novaculite Properties

Know all about Gneiss and Novaculite properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Novaculite belongs to Sedimentary Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Novaculite is Banded, Glassy, Rough, Vitreous. Gneiss appears Foliated and Novaculite appears Glassy or Pearly. The luster of Gneiss is dull while that of Novaculite is waxy and dull. Gneiss is available in black, brown, pink, red, white colors whereas Novaculite is available in black, brown, green, grey, red, white colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Novaculite are cemetery markers, gemstone, in aquifers, in fire-starting tools, jewelry, manufacture of tools, pebbles are used in ball mills to grind in ceramics industry, to determine the gold content of jewelry.