Definition
Rhomb-porphyry is a porphyritic igneous rock with abundant wedge or lens shaped anorthoclase or feldspar phenocrysts
  
Marl is an unconsolidated sedimentary rock consisting of clay and lime
  
History
  
  
Discoverer
Unknown
  
Unknown
  
Etymology
From Latin term that means purple
  
From Old French marle, from Late Latin marglia
  
Class
Igneous Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Soft Rock
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Aphanitic to Porphyritic
  
Earthy
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Beige, Brown, Green, Grey, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
No
  
No
  
Stain Resistant
Yes
  
No
  
Wind Resistant
Yes
  
No
  
Acid Resistant
No
  
No
  
Appearance
Rough
  
Rough and Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
  
Decorative Aggregates, Floor Tiles
  
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
  
As Building Stone, Roof Tiles
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
  
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
  
Artifacts, Jewellery, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Metallurgical Flux, Soil Conditioner, Source of Magnesia (MgO)
  
Creating Artwork, Soil Conditioner
  
Types
Not Available
  
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
Host Rock for Lead
  
Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Not Applicable
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Used
  
Used
  
Fossils
Absent
  
Present
  
Formation
Rhomb-porphyry 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.
  
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
Alkali feldspar, Biotite, Plagioclase, Pyroxene
  
Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz
  
Compound Content
CaO, Cl, MgO
  
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Impact Metamorphism
  
Not Applicable
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion
  
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
5-5.5
  
2-3
  
Grain Size
Fine Grained
  
Very fine-grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Highly Porous
  
Luster
Subvitreous to Dull
  
Dull
  
Compressive Strength
310.00 N/mm
2
  
2
Not Available
  
Cleavage
Perfect
  
Not Available
  
Toughness
2.7
  
2.6
  
Specific Gravity
2.86
  
2.2-2.8
  
Transparency
Translucent
  
Opaque
  
Density
2.8-2.9 g/cm3
  
2.4-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
Not Available
  
Resistance
Heat Resistant, Pressure Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
Not Yet Found
  
India, Pakistan, Russia
  
Africa
Not Yet Found
  
Ethiopia, Kenya, Morocco, South Africa
  
Europe
Bulgaria
  
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
USA
  
USA
  
South America
Not Yet Found
  
Colombia, Ecuador, Peru
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
New South Wales, Victoria, Western Australia