Definition
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
  
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
  
History
  
  
Origin
USA
  
England
  
Discoverer
Unknown
  
Unknown
  
Etymology
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
  
From Old French esclate, from esclat (French éclat)
  
Class
Igneous Rocks
  
Metamorphic 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
  
Foliated
  
Color
Black to Grey, Dark Greenish - Grey
  
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
  
Maintenance
More
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Skeletal
  
Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
  
Exterior Uses
As Building Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
  
As Dimension Stone
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates
  
Types
Not Available
  
Not Available
  
Features
Available in Lots of Colors and Patterns
  
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Used
  
Famous Monuments
Not Applicable
  
Data Not Available
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Absent
  
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.
  
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
  
Composition
  
  
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
  
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
  
Compound Content
Ca, Fe, Potassium Oxide, NA, Potassium, Silicon Dioxide
  
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
  
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
  
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
5.5-6
  
3-4
  
Grain Size
Fine Grained
  
Very fine-grained
  
Fracture
Conchoidal
  
Splintery
  
Streak
Black
  
Light to dark brown
  
Porosity
Less Porous
  
Less Porous
  
Luster
Greasy to Dull
  
Dull
  
Compressive Strength
200.50 N/mm2
  
9
30.00 N/mm2
  
30
Cleavage
Not Available
  
Slaty
  
Toughness
2.1
  
1.2
  
Specific Gravity
2.34-2.40
  
2.65-2.8
  
Transparency
Opaque
  
Opaque
  
Density
Not Available
  
2.6-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
1.12 kJ/Kg K
  
7
0.76 kJ/Kg K
  
17
Resistance
Heat Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
  
China, India, Turkey
  
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
  
Not Yet Found
  
Europe
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland
  
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
  
Others
Not Yet Found
  
Arctic
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
USA
  
South America
Not Yet Found
  
Brazil
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
Not Yet Found
  
Rhyodacite vs Slate 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. Rhyodacite vs Slate characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rhyodacite and Properties of Slate. Learn more about Rhyodacite vs Slate in the next section. The interior uses of Rhyodacite include Decorative aggregates and Interior decoration whereas the interior uses of Slate include Bathrooms, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads. Due to some exceptional properties of Rhyodacite and Slate, they have various applications in construction industry. The uses of Rhyodacite in construction industry include As dimension stone, Construction aggregate, For road aggregate, Landscaping and that of Slate include As dimension stone.
More about Rhyodacite and Slate
Here you can know more about Rhyodacite and Slate. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rhyodacite and Slate consists of mineral content and compound content. The mineral content of Rhyodacite includes Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon and mineral content of Slate includes Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Rhyodacite vs Slate, the texture, color and appearance plays an important role in determining the type of rock. Rhyodacite is available in black to grey, dark greenish - grey colors whereas, Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors. Appearance of Rhyodacite is Skeletal and that of Slate is Dull. Properties of rock is another aspect for Rhyodacite vs Slate. The hardness of Rhyodacite is 5.5-6 and that of Slate is 3-4. The types of Rhyodacite are Not Available whereas types of Slate are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Rhyodacite is black while that of Slate is light to dark brown. The specific heat capacity of Rhyodacite is 1.12 kJ/Kg K and that of Slate is 0.76 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Rhyodacite is heat resistant whereas Slate is heat resistant, impact resistant, pressure resistant, wear resistant.