Definition
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
  
Limestone is a sedimentary rock composed mostly of calcite and aragonite, which are different crystal forms of calcium carbonate
  
History
  
  
Origin
USA
  
New Zealand
  
Discoverer
Unknown
  
Belsazar Hacquet
  
Etymology
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
  
From lime and stone in late 14th Century
  
Class
Igneous Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Earthy
  
Clastic or Non-Clastic
  
Color
Black to Grey, Dark Greenish - Grey
  
Beige, Black, Blue, Brown, Cream, Gold, Green, Grey, Light Green, Light Grey, Linen, Pink, Red, Rust, Silver, White, Yellow
  
Maintenance
More
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
No
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Skeletal
  
Rough and Banded
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
  
Cement Manufacture, Cobblestones, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar, Roadstone, Source of calcium
  
Medical Industry
Not Yet Used
  
In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
  
Antiquity Uses
Artifacts
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Animal feed filler, As a Feed Additive for Livestock, Paper Industry, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Used in aquariums, Whiting material in toothpaste, paint and paper
  
Types
Not Available
  
Chalk, Coquina, Fossiliferous Limestone, Lithographic Limestone, Oolitic Limestone, Travertine, Tufa
  
Features
Available in Lots of Colors and Patterns
  
Host Rock for Lead, Stalactites and stalagmites are formed from this rock, Zinc and Copper Deposits
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Used
  
Famous Monuments
Not Applicable
  
Acropolis of Athens in Greece, Agia Sophia in Istanbul, Turkey, Al Aqsa Mosque in Jerusalem, Angkor Wat in Cambodia, Big Ben in London, Charminar in Hyderabad, India, Chhatrapati Shivaji Terminus in Maharashtra, India, Chichen Itza in Mexico, Empire State Building in New York, Khajuraho Temples, India, Kremlin in Moscow, Louvre in Paris, France, Neuschwanstein in Bavaria, Potala Palace in Lahasa, Tibet, Wailing Wall in Jerusalem
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Ajanta Caves in Maharashtra, India, Elephanta Caves in Maharashtra, India
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Present
  
Formation
Rhyodacite 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.
  
Limestone is a sedimentary rock which is mainly made up of calcium carbonate.
  
Composition
  
  
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
  
Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt
  
Compound Content
Ca, Fe, Potassium Oxide, NA, Potassium, Silicon Dioxide
  
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, MgO
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Chemical Erosion, Coastal Erosion
  
Physical Properties
  
  
Hardness
5.5-6
  
3-4
  
Grain Size
Fine Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Splintery
  
Streak
Black
  
White
  
Porosity
Less Porous
  
Less Porous
  
Luster
Greasy to Dull
  
Dull to Pearly
  
Compressive Strength
200.50 N/mm2
  
9
115.00 N/mm2
  
18
Cleavage
Not Available
  
Non-Existent
  
Toughness
2.1
  
1
  
Specific Gravity
2.34-2.40
  
2.3-2.7
  
Transparency
Opaque
  
Opaque
  
Density
Not Available
  
2.3-2.7 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
1.12 kJ/Kg K
  
7
0.91 kJ/Kg K
  
11
Resistance
Heat Resistant
  
Pressure Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
  
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
  
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
  
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
  
Europe
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland
  
United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
USA
  
South America
Not Yet Found
  
Colombia
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
Adelaide, New Zealand, Queensland, Tonga, Victoria, Yorke Peninsula
  
All about Rhyodacite and Limestone Properties
Know all about Rhyodacite and Limestone properties here. All properties of rocks are important as they define the type of rock and its application. Rhyodacite belongs to Igneous Rocks while Limestone belongs to Sedimentary Rocks.Texture of Rhyodacite is Earthy whereas that of Limestone is Clastic or Non-Clastic. Rhyodacite appears Skeletal and Limestone appears Rough and Banded. The luster of Rhyodacite is greasy to dull while that of Limestone is dull to pearly. Rhyodacite is available in black to grey, dark greenish - grey colors whereas Limestone is available in beige, black, blue, brown, cream, gold, green, grey, light green, light grey, linen, pink, red, rust, silver, white, yellow colors. The commercial uses of Rhyodacite are cemetery markers, creating artwork and that of Limestone are animal feed filler, as a feed additive for livestock, paper industry, raw material for manufacture of quicklime, slaked lime, soil conditioner, used in aquariums, whiting material in toothpaste, paint and paper.