Definition
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Discoverer
Unknown
Unknown
Etymology
From English feldspar and -ite
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Arborescent Patterned, Vitreous
Clastic or Non-Clastic
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Grey, White, Yellow
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Soft
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Powder
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, raw material for manufacture of quicklime and slaked lime, Source of calcium
Medical Industry
Surgery
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Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Mirror, Jewelry
Alumina Refineries, Creating Artwork, Drawing on blackboards, Gymnasts, athletes and mountain climbers use for grip, In aquifers, Paper Industry, Production of Lime, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Whiting, Whiting material in toothpaste, paint and paper
Types
Igneous rock
Chalk Marl and Marl
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Archaeological Significance
Formation
Felsite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Mineral Content
Feldspar, Iron Oxides
Calcite, Clay, Clay Minerals, Quartz, Sand
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, NaCl, CaO
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Fine Grained
Very fine-grained
Porosity
Very Less Porous
Highly Porous
Specific Gravity
2.6-2.7
2.3-2.4
Transparency
Translucent
Opaque
Density
2.6 g/cm3
2.49-2.50 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Africa
Kenya
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Europe
Greece, Hungary, Iceland, Italy, Turkey
England, France, Germany, Spain, United Kingdom
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Argentina, Chile, Ecuador, Peru
Colombia
Deposits in Oceania Continent
Australia
New Zealand
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
Felsite vs Chalk Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Felsite vs Chalk characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Felsite and Properties of Chalk. Learn more about Felsite vs Chalk in the next section. The interior uses of Felsite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Chalk include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Felsite and Chalk, they have various applications in construction industry. The uses of Felsite in construction industry include Arrowheads, Cutting tool, Knives, Scrapers, Spear points and that of Chalk include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for manufacture of quicklime and slaked lime, Source of calcium.
More about Felsite and Chalk
Here you can know more about Felsite and Chalk. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Felsite and Chalk consists of mineral content and compound content. The mineral content of Felsite includes Feldspar, Iron Oxides and mineral content of Chalk includes Calcite, Clay, Clay Minerals, Quartz, Sand. You can also check out the list of all Igneous Rocks. When we have to compare Felsite vs Chalk, the texture, color and appearance plays an important role in determining the type of rock. Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors whereas, Chalk is available in grey, white, yellow colors. Appearance of Felsite is Layered, Banded, Veined and Shiny and that of Chalk is Soft. Properties of rock is another aspect for Felsite vs Chalk. The hardness of Felsite is 5-5.5 and that of Chalk is 1. The types of Felsite are Igneous rock whereas types of Chalk are Chalk Marl and Marl. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Felsite and Chalk is white. The specific heat capacity of Felsite is 0.92 kJ/Kg K and that of Chalk is 0.90 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Felsite is heat resistant, impact resistant whereas Chalk is heat resistant.